C# 上传文件

http://www.cnblogs.com/QLJ1314/archive/2013/03/04/2942703.html

有个博友问多个文件上传的问题,正好最近我也遇见这样的问题,刚好解决,费了好大的劲儿呀!终于皇天不负有心人啊,写到上边也让自己记住,希望这对那位博友有所帮助吧,也希望各位大牛看到后提出意见。大家互相学习,共同努力,加油!好了废话不多说了,开始吧,上例子。

1.最简单的单文件上传(没花头)

效果图:

说明:这是最基本的文件上传,在asp.Net1.x中没有这个FileUpload控件,只有html的上传控件,那时候要把html控件转化为服务器控件,很不好用。其实所有文件上传的美丽效果都是从这个FileUpload控件衍生,第一个例子虽然简单却是根本。

后台代码:
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{

}
protected void bt_upload_Click(object sender, EventArgs e)
{
try
{
if (FileUpload1.PostedFile.FileName == "")
{
this.lb_info.Text = "请选择文件!";
}
else
{
string filepath = FileUpload1.PostedFile.FileName;
string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);
string serverpath = Server.MapPath("images/") + filename;
FileUpload1.PostedFile.SaveAs(serverpath);
this.lb_info.Text = "上传成功!";
}
}
catch (Exception ex)
{
this.lb_info.Text = "上传发生错误!原因是:" + ex.ToString();
}
}
}

前台代码:
<table style="width: 343px">
<tr>
<td style="width: 100px">
单文件上传</td>
<td style="width: 100px">
</td>
</tr>
<tr>
<td style="width: 100px">
<asp:FileUpload ID="FileUpload1" runat="server" Width="475px" />
</td>
<td style="width: 100px">
<asp:Button ID="bt_upload" runat="server" OnClick="bt_upload_Click" Text="上传" /></td>
</tr>
<tr>
<td style="width: 100px; height: 21px;">
<asp:Label ID="lb_info" runat="server" ForeColor="Red" Width="183px"></asp:Label></td>
<td style="width: 100px; height: 21px">
</td>
</tr>
</table>

2.多文件上传

效果图:


后台代码:
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{

}
protected void bt_upload_Click(object sender, EventArgs e)
{

if ((FileUpload1.PostedFile.FileName == "" && FileUpload2.PostedFile.FileName == "")&&FileUpload3.PostedFile.FileName == "")
{
this.lb_info.Text = "请选择文件!";
}
else
{
HttpFileCollection myfiles = Request.Files;
for (int i = 0; i < myfiles.Count; i++)
{
HttpPostedFile mypost = myfiles[i];
try
{
if (mypost.ContentLength > 0)
{
string filepath = mypost.FileName;
string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);
string serverpath = Server.MapPath("images/") + filename;
mypost.SaveAs(serverpath);
this.lb_info.Text = "上传成功!";
}
}
catch (Exception error)
{
this.lb_info.Text = "上传发生错误!原因:" + error.ToString();
}

}

}
}

}

前台代码:
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html Xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>多文件上传 清清月儿http://blog.csdn.Net/21as.Net/</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<table style="width: 343px">
<tr>
<td style="width: 100px">
多文件上传</td>
<td style="width: 100px">
</td>
</tr>
<tr>
<td style="width: 100px">
<asp:FileUpload ID="FileUpload1" runat="server" Width="475px" />
</td>
<td style="width: 100px">
</td>
</tr>
<tr>
<td style="width: 100px">
<asp:FileUpload ID="FileUpload2" runat="server" Width="475px" /></td>
<td style="width: 100px">
</td>
</tr>
<tr>
<td style="width: 100px">
<asp:FileUpload ID="FileUpload3" runat="server" Width="475px" /></td>
<td style="width: 100px">
</td>
</tr>
<tr>
<td style="width: 100px">
<asp:Button ID="bt_upload" runat="server" OnClick="bt_upload_Click" Text="一起上传" />
<asp:Label ID="lb_info" runat="server" ForeColor="Red" Width="183px"></asp:Label></td>
<td style="width: 100px">
</td>
</tr>
</table>

</div>
</form>
</body>
</html>

3.客户端检查上传文件类型(以上传图片为例)

效果图:

后台代码和1.最简单的单文件上传一样;
前台代码:
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html Xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>清清月儿 .Net/21as.Nethttp://blog.csdn.Net/21as.Net</title>
<script language="Javascript">
function Check_FileType()
{
var str=document.getElementById("FileUpload1").value;
var pos = str.lastIndexOf(".");
var lastname = str.substring(pos,str.length)
if (lastname.toLowerCase()!=".jpg" && lastname.toLowerCase()!=".gif")
{
alert("您上传的文件类型为"+lastname+",图片必须为.jpg,.gif类型");
return false;
}
else
{
return true;
}
}
</script>

</head>
<body>
<form id="form1" runat="server">
<div>
<table style="width: 343px">
<tr>
<td style="width: 104px">
文件上传判断</td>
<td style="width: 100px">
</td>
</tr>
<tr>
<td style="width: 104px">
<asp:FileUpload ID="FileUpload1" runat="server" Width="400px" />
</td>
<td style="width: 100px">
<asp:Button ID="bt_upload" runat="server" OnClick="bt_upload_Click" Text="上传" OnClientClick="return Check_FileType()"/></td>
</tr>
<tr>
<td style="width: 104px; height: 21px;">
<asp:Label ID="lb_info" runat="server" ForeColor="Red" Width="183px"></asp:Label></td>
<td style="width: 100px; height: 21px">
</td>
</tr>
</table>

</div>
</form>
</body>
</html>
说明:点击上传时先触发客户端事件Check_FileType;

4.服务器端检查上传文件类型(以上传图片为例)

效果图:


后台代码:
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{

}
protected void bt_upload_Click(object sender, EventArgs e)
{
try
{
if (FileUpload1.PostedFile.FileName == "")
{
this.lb_info.Text = "请选择文件!";
}
else
{
string filepath = FileUpload1.PostedFile.FileName;
if (IsAllowedExtension(FileUpload1) == true)
{

string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);
string serverpath = Server.MapPath("images/") + filename;
FileUpload1.PostedFile.SaveAs(serverpath);
this.lb_info.Text = "上传成功!";
}
else
{
this.lb_info.Text = "请上传图片";
}
}
}
catch (Exception error)
{
this.lb_info.Text = "上传发生错误!原因:" + error.ToString();
}
}
public static bool IsAllowedExtension(FileUpload hifile)
{
string strOldFilePath = "", strExtension = "";
string[] arrExtension = { ".gif", ".jpg", ".jpeg", ".bmp", ".png" };
if (hifile.PostedFile.FileName != string.Empty)
{
strOldFilePath = hifile.PostedFile.FileName;
strExtension = strOldFilePath.Substring(strOldFilePath.LastIndexOf("."));
for (int i = 0; i < arrExtension.Length; i++)
{
if (strExtension.Equals(arrExtension[i]))
{
return true;
}
}
}
return false;
}

}


5.服务器端检查上传文件类型(可以检测真正文件名)
其实方法4并不好,因为用户可以把XXX.txt伪装为XXX.jpg。

效果图:


后台代码:
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class _Default : System.Web.UI.Page
{
//清清月儿 http://blog.csdn.Net/21as.Net
protected void Page_Load(object sender, EventArgs e)
{

}
protected void bt_upload_Click(object sender, EventArgs e)
{
try
{
if (FileUpload1.PostedFile.FileName == "")
{
this.lb_info.Text = "请选择文件!";
}
else
{
string filepath = FileUpload1.PostedFile.FileName;
if (IsAllowedExtension(FileUpload1) == true)
{
string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);
string serverpath = Server.MapPath("images/") + filename;
FileUpload1.PostedFile.SaveAs(serverpath);
this.lb_info.Text = "上传成功!";
}
else
{
this.lb_info.Text = "请上传图片";
}
}
}
catch (Exception error)
{
this.lb_info.Text = "上传发生错误!原因:" + error.ToString();
}
}
public static bool IsAllowedExtension(FileUpload hifile)
{
System.IO.FileStream fs = new System.IO.FileStream(hifile.PostedFile.FileName, System.IO.FileMode.Open, System.IO.FileAccess.Read);
System.IO.BinaryReader r = new System.IO.BinaryReader(fs);
string fileclass = "";
byte buffer;
try
{
buffer = r.ReadByte();
fileclass = buffer.ToString();
buffer = r.ReadByte();
fileclass += buffer.ToString();

}
catch
{

}
r.Close();
fs.Close();
if (fileclass == "255216" || fileclass == "7173")//说明255216是jpg;7173是gif;6677是BMP,13780是PNG;7790是exe,8297是rar
{
return true;
}
else
{
return false;
}

}

}

6.上传文件文件名唯一性处理(时间戳+SessionID)

效果图:

说明:年月日时分秒+临时session+原文件名 如果大家怕还会重复可以加GUID
后台代码:


try
{
if (FileUpload1.PostedFile.FileName == "")
{
this.lb_info.Text = "请选择文件!";
}
else
{
string filepath = FileUpload1.PostedFile.FileName;
string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);
string serverpath = Server.MapPath("images/") + System.DateTime.Now.ToString("yyy-MM-dd-hh-mm-ss") + Session.SessionID + filename;
FileUpload1.PostedFile.SaveAs(serverpath);
this.lb_info.Text = "上传成功!";
}
}
catch (Exception error)
{
this.lb_info.Text = "上传发生错误!原因:" + error.ToString();
}

注:GUID的方法:Guid myGuid=Guid.NewGuid();

7.上传图片生成等比例缩略图

效果图:


缩略图代码:
ImageThumbnail.cs
using System;
using System.IO;
using System.Drawing;
using System.Drawing.Imaging;

public class ImageThumbnail
{
public Image ResourceImage;
private int ImageWidth;
private int ImageHeight;
public string ErrorMessage;

public ImageThumbnail(string ImageFileName)
{
ResourceImage = Image.FromFile(ImageFileName);
ErrorMessage = "";
}

public bool ThumbnailCallback()
{
return false;
}


// 方法1,按大小
public bool ReducedImage(int Width, int Height, string targetFilePath)
{
try
{
Image ReducedImage;
Image.GetThumbnailImageAbort callb = new Image.GetThumbnailImageAbort(ThumbnailCallback);
ReducedImage = ResourceImage.GetThumbnailImage(Width, Height, callb, IntPtr.Zero);
ReducedImage.Save(@targetFilePath, ImageFormat.Jpeg);
ReducedImage.Dispose();
return true;
}
catch (Exception e)
{
ErrorMessage = e.Message;
return false;
}
}


// 方法2,按百分比 缩小60% Percent为0.6 targetFilePath为目标路径
public bool ReducedImage(double Percent, string targetFilePath)
{
try
{
Image ReducedImage;
Image.GetThumbnailImageAbort callb = new Image.GetThumbnailImageAbort(ThumbnailCallback);
ImageWidth = Convert.ToInt32(ResourceImage.Width * Percent);
ImageHeight = (ResourceImage.Height)*ImageWidth/ ResourceImage.Width;//等比例缩放
ReducedImage = ResourceImage.GetThumbnailImage(ImageWidth, ImageHeight, callb, IntPtr.Zero);
ReducedImage.Save(@targetFilePath, ImageFormat.Jpeg);
ReducedImage.Dispose();
return true;
}
catch (Exception e)
{
ErrorMessage = e.Message;
return false;
}
}


}

后台代码:
using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
public partial class _Default : System.Web.UI.Page
{

protected void Page_Load(object sender, EventArgs e)
{

}
protected void bt_upload_Click(object sender, EventArgs e)
{
try
{
if (FileUpload1.PostedFile.FileName == "")
{
this.lb_info.Text = "请选择文件!";
}
else
{
string filepath = FileUpload1.PostedFile.FileName;
string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);
string serverpath1 = Server.MapPath("images/") + filename;
string serverpath2 = Server.MapPath("images/") + System.DateTime.Now.ToString("yyy-MM-dd-hh-mm-ss") + Session.SessionID + filename;
FileUpload1.PostedFile.SaveAs(serverpath1);
ImageThumbnail img = new ImageThumbnail(filepath);
img.ReducedImage(0.4, serverpath2);//0.4表示缩小40%
this.lb_info.Text = "上传成功!";
}
}
catch (Exception error)
{
this.lb_info.Text = "上传发生错误!原因:" + error.ToString();
}
}


}

8.上传图片加水印(文字水印,图片水印,文字+图片水印)

效果图:
原图

水印

给图片加水印以后(注意右上角+正下方)


代码:
DrawImg.cs 出自http://www.codeproject.com/csharp/watermark.asp
using System;
using System.Drawing;
using System.Drawing.Imaging;
using System.Drawing.Drawing2D;
public class DrawImg
{
private string WorkingDirectory = string.Empty ; //路径
private string ImageName = string.Empty; //被处理的图片
private string ImageWater = string.Empty; //水印图片
private string FontString = string.Empty; //水印文字

enum DealType{NONE,WaterImage,WaterFont,DoubleDo}; //枚举命令

private DealType dealtype;

public DrawImg()
{}

public string PublicWorkingDirectory
{
get
{
return WorkingDirectory;
}
set
{
WorkingDirectory = value;
}
}

public string PublicImageName
{
get
{
return ImageName;
}
set
{
ImageName = value;
}
}


public string PublicImageWater
{
get
{
return ImageWater;
}
set //设置了水印图片的话说明是要水印图片效果的
{
dealtype = DealType.WaterImage;
ImageWater = value;
}
}

public string PublicFontString
{
get
{
return FontString;
}
set //设置了水印文字的话说明是要水印文字效果的
{
dealtype = DealType.WaterFont;
FontString = value;
}
}

 

public void DealImage()
{
IsDouble();

switch( dealtype )
{
case DealType.WaterFont: WriteFont(); break;
case DealType.WaterImage: WriteImg(); break;
case DealType.DoubleDo: WriteFontAndImg(); break;
}

}

private void IsDouble()
{
if(ImageWater+""!="" && FontString+""!="")
{
dealtype = DealType.DoubleDo;
}
}

private void WriteFont()
{
//set a working directory
//string WorkingDirectory = @"C:\Watermark_src\WaterPic";

//define a string of text to use as the Copyright message
//string Copyright = "Copyright ?2002 - AP Photo/David Zalubowski";

//create a image object containing the photograph to watermark
Image imgPhoto = Image.FromFile(WorkingDirectory + ImageName);
int phWidth = imgPhoto.Width;
int phHeight = imgPhoto.Height;

//create a Bitmap the Size of the original photograph
Bitmap bmPhoto = new Bitmap(phWidth, phHeight, PixelFormat.Format24bppRgb);

bmPhoto.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);

//load the Bitmap into a Graphics object
Graphics grPhoto = Graphics.FromImage(bmPhoto);

//------------------------------------------------------------
//Step #1 - Insert Copyright message
//------------------------------------------------------------

//Set the rendering quality for this Graphics object
grPhoto.SmoothingMode = SmoothingMode.AntiAlias;

//Draws the photo Image object at original size to the graphics object.
grPhoto.DrawImage(
imgPhoto, // Photo Image object
new Rectangle(0, 0, phWidth, phHeight), // Rectangle structure
0, // x-coordinate of the portion of the source image to draw.
0, // y-coordinate of the portion of the source image to draw.
phWidth, // Width of the portion of the source image to draw.
phHeight, // Height of the portion of the source image to draw.
GraphicsUnit.Pixel); // Units of measure

//-------------------------------------------------------
//to maximize the size of the Copyright message we will
//test multiple Font sizes to determine the largest posible
//font we can use for the width of the Photograph
//define an array of point sizes you would like to consider as possiblities
//-------------------------------------------------------
int[] sizes = new int[]{16,14,12,10,8,6,4};

Font crFont = null;
SizeF crSize = new SizeF();

//Loop through the defined sizes checking the length of the Copyright string
//If its length in pixles is less then the image width choose this Font size.
for (int i=0 ;i<7; i++)
{
//set a Font object to Arial (i)pt, Bold
//crFont = new Font("arial", sizes[i], FontStyle.Bold);

crFont = new Font("arial",sizes[i],FontStyle.Bold);

//Measure the Copyright string in this Font
crSize = grPhoto.MeasureString(FontString, crFont);

if((ushort)crSize.Width < (ushort)phWidth)
break;
}

//Since all photographs will have varying heights, determine a
//position 5% from the bottom of the image
int yPixlesFromBottom = (int)(phHeight *.05);

//Now that we have a point size use the Copyrights string height
//to determine a y-coordinate to draw the string of the photograph
float yPosFromBottom = ((phHeight - yPixlesFromBottom)-(crSize.Height/2));

//Determine its x-coordinate by calculating the center of the width of the image
float xCenterOfImg = (phWidth/2);

//Define the text layout by setting the text alignment to centered
StringFormat StrFormat = new StringFormat();
StrFormat.Alignment = StringAlignment.Center;

//define a Brush which is semi trasparent black (Alpha set to 153)
SolidBrush semiTransBrush2 = new SolidBrush(Color.FromArgb(153, 0, 0, 0));

//Draw the Copyright string
grPhoto.DrawString(FontString, //string of text
crFont, //font
semiTransBrush2, //Brush
new PointF(xCenterOfImg+1,yPosFromBottom+1), //Position
StrFormat);

//define a Brush which is semi trasparent white (Alpha set to 153)
SolidBrush semiTransBrush = new SolidBrush(Color.FromArgb(153, 255, 255, 255));

//Draw the Copyright string a second time to create a shadow effect
//Make sure to move this text 1 pixel to the right and down 1 pixel
grPhoto.DrawString(FontString, //string of text
crFont, &nb, sp; //font
semiTransBrush, //Brush
new PointF(xCenterOfImg,yPosFromBottom), //Position
StrFormat);

imgPhoto = bmPhoto;
grPhoto.Dispose();

//save new image to file system.
imgPhoto.Save(WorkingDirectory + ImageName + "_finally.jpg", ImageFormat.Jpeg);
imgPhoto.Dispose();

//Text alignment
}


private void WriteImg()
{
//set a working directory
//string WorkingDirectory = @"C:\Watermark_src\WaterPic";

//create a image object containing the photograph to watermark
Image imgPhoto = Image.FromFile(WorkingDirectory + ImageName);
int phWidth = imgPhoto.Width;
int phHeight = imgPhoto.Height;

//create a Bitmap the Size of the original photograph
Bitmap bmPhoto = new Bitmap(phWidth, phHeight, PixelFormat.Format24bppRgb);

bmPhoto.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);

//load the Bitmap into a Graphics object
Graphics grPhoto = Graphics.FromImage(bmPhoto);

//create a image object containing the watermark
Image imgWatermark = new Bitmap(WorkingDirectory + ImageWater);
int wmWidth = imgWatermark.Width;
int wmHeight = imgWatermark.Height;

//Set the rendering quality for this Graphics object
grPhoto.SmoothingMode = SmoothingMode.AntiAlias;

//Draws the photo Image object at original size to the graphics object.
grPhoto.DrawImage(
imgPhoto, // Photo Image object
new Rectangle(0, 0, phWidth, phHeight), // Rectangle structure
0, // x-coordinate of the portion of the source image to draw.
0, // y-coordinate of the portion of the source image to draw.
phWidth, // Width of the portion of the source image to draw.
phHeight, // Height of the portion of the source image to draw.
GraphicsUnit.Pixel); // Units of measure


//------------------------------------------------------------
//Step #2 - Insert Watermark image
//------------------------------------------------------------

//Create a Bitmap based on the previously modified photograph Bitmap
Bitmap bmWatermark = new Bitmap(bmPhoto);
bmWatermark.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);
//Load this Bitmap into a new Graphic Object
Graphics grWatermark = Graphics.FromImage(bmWatermark);

//To achieve a transulcent watermark we will apply (2) color
//manipulations by defineing a ImageAttributes object and
//seting (2) of its properties.
ImageAttributes imageAttributes = new ImageAttributes();

//The first step in manipulating the watermark image is to replace
//the background color with one that is trasparent (Alpha=0, R=0, G=0, B=0)
//to do this we will use a Colormap and use this to define a RemapTable
ColorMap colorMap = new ColorMap();

//My watermark was defined with a background of 100% Green this will
//be the color we search for and replace with transparency
colorMap.OldColor = Color.FromArgb(255, 0, 255, 0);
colorMap.NewColor = Color.FromArgb(0, 0, 0, 0);

ColorMap[] remapTable = {colorMap};

imageAttributes.SetRemapTable(remapTable, ColorAdjustType.Bitmap);

//The second color manipulation is used to change the opacity of the
//watermark. This is done by applying a 5x5 matrix that contains the
//coordinates for the RGBA space. By setting the 3rd row and 3rd column
//to 0.3f we achive a level of opacity
float[][] colorMatrixElements = {
new float[] {1.0f, 0.0f, 0.0f, 0.0f, 0.0f},
new float[] {0.0f, 1.0f, 0.0f, 0.0f, 0.0f},
new float[] {0.0f, 0.0f, 1.0f, 0.0f, 0.0f},
new float[] {0.0f, 0.0f, 0.0f, 0.3f, 0.0f},
new float[] {0.0f, 0.0f, 0.0f, 0.0f, 1.0f}};
ColorMatrix wmColorMatrix = new ColorMatrix(colorMatrixElements);

imageAttributes.SetColorMatrix(wmColorMatrix, ColorMatrixFlag.Default,
ColorAdjustType.Bitmap);

//For this example we will place the watermark in the upper right
//hand corner of the photograph. offset down 10 pixels and to the
//left 10 pixles

int xPosOfWm = ((phWidth - wmWidth)-10);
int yPosOfWm = 10;

grWatermark.DrawImage(imgWatermark,
new Rectangle(xPosOfWm,yPosOfWm,wmWidth,wmHeight), //Set the detination Position
0, // x-coordinate of the portion of the source image to draw.
0, // y-coordinate of the portion of the source image to draw.
wmWidth, // Watermark Width
wmHeight, // Watermark Height
GraphicsUnit.Pixel, // Unit of measurment
imageAttributes); //ImageAttributes Object

//Replace the original photgraphs bitmap with the new Bitmap
imgPhoto = bmWatermark;
grPhoto.Dispose();
grWatermark.Dispose();

//save new image to file system.
imgPhoto.Save(WorkingDirectory + ImageName +"_finally.jpg", ImageFormat.Jpeg);
imgPhoto.Dispose();
imgWatermark.Dispose();

}


private void WriteFontAndImg()
{

//create a image object containing the photograph to watermark
Image imgPhoto = Image.FromFile(WorkingDirectory + ImageName);
int phWidth = imgPhoto.Width;
int phHeight = imgPhoto.Height;

//create a Bitmap the Size of the original photograph
Bitmap bmPhoto = new Bitmap(phWidth, phHeight, PixelFormat.Format24bppRgb);

bmPhoto.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);

//load the Bitmap into a Graphics object
Graphics grPhoto = Graphics.FromImage(bmPhoto);

//create a image object containing the watermark
Image imgWatermark = new Bitmap(WorkingDirectory + ImageWater);
int wmWidth = imgWatermark.Width;
int wmHeight = imgWatermark.Height;

//------------------------------------------------------------
//Step #1 - Insert Copyright message
//------------------------------------------------------------

//Set the rendering quality for this Graphics object
grPhoto.SmoothingMode = SmoothingMode.AntiAlias;

//Draws the photo Image object at original size to the graphics object.
grPhoto.DrawImage(
imgPhoto, // Photo Image object
new Rectangle(0, 0, phWidth, phHeight), // Rectangle structure
0, // x-coordinate of the portion of the source image to draw.
0, // y-coordinate of the portion of the source image to draw.
phWidth, // Width of the portion of the source image to draw.
phHeight, // Height of the portion of the source image to draw.
GraphicsUnit.Pixel); // Units of measure

//-------------------------------------------------------
//to maximize the size of the Copyright message we will
//test multiple Font sizes to determine the largest posible
//font we can use for the width of the Photograph
//define an array of point sizes you would like to consider as possiblities
//-------------------------------------------------------
int[] sizes = new int[]{16,14,12,10,8,6,4};

Font crFont = null;
SizeF crSize = new SizeF();

//Loop through the defined sizes checking the length of the Copyright string
//If its length in pixles is less then the image width choose this Font size.
for (int i=0 ;i<7; i++)
{
//set a Font object to Arial (i)pt, Bold
crFont = new Font("arial", sizes[i], FontStyle.Bold);
//Measure the Copyright string in this Font
crSize = grPhoto.MeasureString(FontString, crFont);

if((ushort)crSize.Width < (ushort)phWidth)
break;
}

//Since all photographs will have varying heights, determine a
//position 5% from the bottom of the image
int yPixlesFromBottom = (int)(phHeight *.05);

//Now that we have a point size use the Copyrights string height
//to determine a y-coordinate to draw the string of the photograph
float yPosFromBottom = ((phHeight - yPixlesFromBottom)-(crSize.Height/2));

//Determine its x-coordinate by calculating the center of the width of the image
float xCenterOfImg = (phWidth/2);

//Define the text layout by setting the text alignment to centered
StringFormat StrFormat = new StringFormat();
StrFormat.Alignment = StringAlignment.Center;

//define a Brush which is semi trasparent black (Alpha set to 153)
SolidBrush semiTransBrush2 = new SolidBrush(Color.FromArgb(153, 0, 0, 0));

//Draw the Copyright string
grPhoto.DrawString(FontString, //string of text
crFont, //font
semiTransBrush2, //Brush
new PointF(xCenterOfImg+1,yPosFromBottom+1), //Position
StrFormat);

//define a Brush which is semi trasparent white (Alpha set to 153)
SolidBrush semiTransBrush = new SolidBrush(Color.FromArgb(153, 255, 255, 255));

//Draw the Copyright string a second time to create a shadow effect
//Make sure to move this text 1 pixel to the right and down 1 pixel
grPhoto.DrawString(FontString, //string of text
crFont, //font
semiTransBrush, //Brush
new PointF(xCenterOfImg,yPosFromBottom), //Position
StrFormat); //Text alignment

 

//------------------------------------------------------------
//Step #2 - Insert Watermark image
//------------------------------------------------------------

//Create a Bitmap based on the previously modified photograph Bitmap
Bitmap bmWatermark = new Bitmap(bmPhoto);
bmWatermark.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);
//Load this Bitmap into a new Graphic Object
Graphics grWatermark = Graphics.FromImage(bmWatermark);

//To achieve a transulcent watermark we will apply (2) color
//manipulations by defineing a ImageAttributes object and
//seting (2) of its properties.
ImageAttributes imageAttributes = new ImageAttributes();

//The first step in manipulating the watermark image is to replace
//the background color with one that is trasparent (Alpha=0, R=0, G=0, B=0)
//to do this we will use a Colormap and use this to define a RemapTable
ColorMap colorMap = new ColorMap();

//My watermark was defined with a background of 100% Green this will
//be the color we search for and replace with transparency
colorMap.OldColor = Color.FromArgb(255, 0, 255, 0);
colorMap.NewColor = Color.FromArgb(0, 0, 0, 0);

ColorMap[] remapTable = {colorMap};

imageAttributes.SetRemapTable(remapTable, ColorAdjustType.Bitmap);

//The second color manipulation is used to change the opacity of the
//watermark. This is done by applying a 5x5 matrix that contains the
//coordinates for the RGBA space. By setting the 3rd row and 3rd column
//to 0.3f we achive a level of opacity
float[][] colorMatrixElements = {
new float[] {1.0f, 0.0f, 0.0f, 0.0f, 0.0f},
new float[] {0.0f, 1.0f, 0.0f, 0.0f, 0.0f},
new float[] {0.0f, 0.0f, 1.0f, 0.0f, 0.0f},
new float[] {0.0f, 0.0f, 0.0f, 0.3f, 0.0f},
new float[] {0.0f, 0.0f, 0.0f, 0.0f, 1.0f}};
ColorMatrix wmColorMatrix = new ColorMatrix(colorMatrixElements);

imageAttributes.SetColorMatrix(wmColorMatrix, ColorMatrixFlag.Default,
ColorAdjustType.Bitmap);

//For this example we will place the watermark in the upper right
//hand corner of the photograph. offset down 10 pixels and to the
//left 10 pixles

int xPosOfWm = ((phWidth - wmWidth)-10);
int yPosOfWm = 10;

grWatermark.DrawImage(imgWatermark,
new Rectangle(xPosOfWm,yPosOfWm,wmWidth,wmHeight), //Set the detination Position
0, // x-coordinate of the portion of the source image to draw.
0, // y-coordinate of the portion of the source image to draw.
wmWidth, // Watermark Width
wmHeight, // Watermark Height
GraphicsUnit.Pixel, // Unit of measurment
imageAttributes); //ImageAttributes Object

//Replace the original photgraphs bitmap with the new Bitmap
imgPhoto = bmWatermark;
grPhoto.Dispose();
grWatermark.Dispose();

//save new image to file system.
imgPhoto.Save(WorkingDirectory + ImageName +"_finally.jpg", ImageFormat.Jpeg);
imgPhoto.Dispose();
imgWatermark.Dispose();


}
}


//水印图片加水印文字
// ReDrawImg img = new ReDrawImg();
// img .PublicWorkingDirectory = @"C:\Watermark_src\WaterPic\";
// img .PublicImageName = "watermark_photo.jpg";
// img .PublicImageWater = "watermark.bmp";
// img .PublicFontString = "清清月儿";
// img .DealImage();

//水印文字
ReDrawImg img = new ReDrawImg();
img .PublicWorkingDirectory = @"C:\Watermark_src\WaterPic\";
img .PublicImageName = "watermark_photo.jpg";
img .PublicFontString = @"清清月儿";
img .DealImage();

//水印图片
// ReDrawImg img = new ReDrawImg();
// img .PublicWorkingDirectory = @"C:\Watermark_src\WaterPic\";
// img .PublicImageName = "watermark_photo.jpg";
// img .PublicImageWater = "watermark.bmp";
// img .DealImage();


后台代码:

using System;
using System.Data;
using System.Configuration;
using System.Collections;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
public partial class _Default : System.Web.UI.Page
{

protected void Page_Load(object sender, EventArgs e)
{

}
protected void bt_upload_Click(object sender, EventArgs e)
{
try
{
if (FileUpload1.PostedFile.FileName == "")
{
this.lb_info.Text = "请选择文件!";
}
else
{
string filepath = FileUpload1.PostedFile.FileName;
string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);
string serverpath1 = Server.MapPath("images/") + filename;
//string serverpath2 = Server.MapPath("images/") + System.DateTime.Now.ToString("yyy-MM-dd-hh-mm-ss") + Session.SessionID + filename;
FileUpload1.PostedFile.SaveAs(serverpath1);
//ImageThumbnail img = new ImageThumbnail(filepath);
//img.ReducedImage(0.4, serverpath2);
DrawImg img = new DrawImg();
img.PublicWorkingDirectory = Server.MapPath("images/");
img.PublicImageName = filename;
img.PublicFontString = "http://blog.csdn.Net/21as.Net";
img.PublicImageWater = "yyy.jpg";
img.DealImage();
this.lb_info.Text = "上传成功!";
}
}
catch (Exception error)
{
this.lb_info.Text = "上传发生错误!原因:" + error.ToString();
}
}
}


复制代码
   1 1.最简单的单文件上传(没花头)
   2 
   3 效果图:
   4 
   5 说明:这是最基本的文件上传,在asp.Net1.x中没有这个FileUpload控件,只有html的上传控件,那时候要把html控件转化为服务器控件,很不好用。其实所有文件上传的美丽效果都是从这个FileUpload控件衍生,第一个例子虽然简单却是根本。
   6 
   7 后台代码:
   8 using System;
   9 using System.Data;
  10 using System.Configuration;
  11 using System.Collections;
  12 using System.Web;
  13 using System.Web.Security;
  14 using System.Web.UI;
  15 using System.Web.UI.WebControls;
  16 using System.Web.UI.WebControls.WebParts;
  17 using System.Web.UI.HtmlControls;
  18 
  19 public partial class _Default : System.Web.UI.Page
  20 {
  21     protected void Page_Load(object sender, EventArgs e)
  22     {
  23 
  24     }
  25     protected void bt_upload_Click(object sender, EventArgs e)
  26     {
  27         try
  28         {
  29             if (FileUpload1.PostedFile.FileName == "")
  30             {
  31                 this.lb_info.Text = "请选择文件!";
  32             }
  33             else
  34             {
  35                 string filepath = FileUpload1.PostedFile.FileName;
  36                 string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);
  37                 string serverpath = Server.MapPath("images/") + filename;
  38                 FileUpload1.PostedFile.SaveAs(serverpath);
  39                 this.lb_info.Text = "上传成功!";
  40             }
  41         }
  42         catch (Exception ex)
  43         {
  44             this.lb_info.Text = "上传发生错误!原因是:" + ex.ToString();
  45         }
  46     }
  47 }
  48 
  49 前台代码:
  50  <table style="width: 343px">
  51             <tr>
  52                 <td style="width: 100px">
  53                     单文件上传</td>
  54                 <td style="width: 100px">
  55                 </td>
  56             </tr>
  57             <tr>
  58                 <td style="width: 100px">
  59                     <asp:FileUpload ID="FileUpload1" runat="server" Width="475px" />
  60                     </td>
  61                 <td style="width: 100px">
  62                     <asp:Button ID="bt_upload" runat="server" OnClick="bt_upload_Click" Text="上传" /></td>
  63             </tr>
  64             <tr>
  65                 <td style="width: 100px; height: 21px;">
  66                     <asp:Label ID="lb_info" runat="server" ForeColor="Red" Width="183px"></asp:Label></td>
  67                 <td style="width: 100px; height: 21px">
  68                 </td>
  69             </tr>
  70         </table>
  71 
  72 2.多文件上传
  73 
  74 效果图:
  75 
  76 
  77 后台代码:
  78 using System;
  79 using System.Data;
  80 using System.Configuration;
  81 using System.Collections;
  82 using System.Web;
  83 using System.Web.Security;
  84 using System.Web.UI;
  85 using System.Web.UI.WebControls;
  86 using System.Web.UI.WebControls.WebParts;
  87 using System.Web.UI.HtmlControls;
  88 
  89 public partial class _Default : System.Web.UI.Page
  90 {
  91     protected void Page_Load(object sender, EventArgs e)
  92     {
  93 
  94     }
  95     protected void bt_upload_Click(object sender, EventArgs e)
  96     {
  97         
  98             if ((FileUpload1.PostedFile.FileName == "" && FileUpload2.PostedFile.FileName == "")&&FileUpload3.PostedFile.FileName == "")
  99             {
 100                 this.lb_info.Text = "请选择文件!";
 101             }
 102             else
 103             {
 104                 HttpFileCollection myfiles = Request.Files;
 105                 for (int i = 0; i < myfiles.Count; i++)
 106                 {
 107                     HttpPostedFile mypost = myfiles[i];
 108                     try
 109                     {
 110                         if (mypost.ContentLength > 0)
 111                         {
 112                              string filepath = mypost.FileName;
 113                              string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);
 114                              string serverpath = Server.MapPath("images/") + filename;
 115                              mypost.SaveAs(serverpath);
 116                              this.lb_info.Text = "上传成功!";
 117                         }
 118                     }
 119                     catch (Exception error)
 120                     {
 121                         this.lb_info.Text = "上传发生错误!原因:" + error.ToString();
 122                     }
 123 
 124                 }
 125                
 126             }
 127         }
 128        
 129     }
 130 
 131 前台代码:
 132  <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
 133 
 134 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 135 
 136 <html Xmlns="http://www.w3.org/1999/xhtml" >
 137 <head runat="server">
 138     <title>多文件上传 清清月儿http://blog.csdn.Net/21as.Net/</title>
 139 </head>
 140 <body>
 141     <form id="form1" runat="server">
 142     <div>
 143         <table style="width: 343px">
 144             <tr>
 145                 <td style="width: 100px">
 146                     多文件上传</td>
 147                 <td style="width: 100px">
 148                 </td>
 149             </tr>
 150             <tr>
 151                 <td style="width: 100px">
 152                     <asp:FileUpload ID="FileUpload1" runat="server" Width="475px" />
 153                     </td>
 154                 <td style="width: 100px">
 155                     </td>
 156             </tr>
 157             <tr>
 158                 <td style="width: 100px">
 159                     <asp:FileUpload ID="FileUpload2" runat="server" Width="475px" /></td>
 160                 <td style="width: 100px">
 161                 </td>
 162             </tr>
 163             <tr>
 164                 <td style="width: 100px">
 165                     <asp:FileUpload ID="FileUpload3" runat="server" Width="475px" /></td>
 166                 <td style="width: 100px">
 167                 </td>
 168             </tr>
 169             <tr>
 170                 <td style="width: 100px">
 171                     <asp:Button ID="bt_upload" runat="server" OnClick="bt_upload_Click" Text="一起上传" />
 172                     <asp:Label ID="lb_info" runat="server" ForeColor="Red" Width="183px"></asp:Label></td>
 173                 <td style="width: 100px">
 174                 </td>
 175             </tr>
 176         </table>
 177     
 178     </div>
 179     </form>
 180 </body>
 181 </html>
 182 
 183 3.客户端检查上传文件类型(以上传图片为例)
 184 
 185 效果图:
 186 
 187 后台代码和1.最简单的单文件上传一样;
 188 前台代码:
 189 <%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
 190 
 191 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 192 
 193 <html Xmlns="http://www.w3.org/1999/xhtml" >
 194 <head runat="server">
 195     <title>清清月儿 .Net/21as.Nethttp://blog.csdn.Net/21as.Net</title>
 196 <script   language="Javascript">  
 197  function Check_FileType()
 198 {
 199 var str=document.getElementById("FileUpload1").value;
 200  var pos = str.lastIndexOf(".");
 201  var lastname = str.substring(pos,str.length)  
 202  if (lastname.toLowerCase()!=".jpg" && lastname.toLowerCase()!=".gif")
 203  {
 204      alert("您上传的文件类型为"+lastname+",图片必须为.jpg,.gif类型");
 205      return false;
 206  }
 207  else 
 208  {
 209   return true;
 210  }
 211 } 
 212  </script>  
 213 
 214 </head>
 215 <body>
 216     <form id="form1" runat="server">
 217     <div>
 218         <table style="width: 343px">
 219             <tr>
 220                 <td style="width: 104px">
 221                     文件上传判断</td>
 222                 <td style="width: 100px">
 223                 </td>
 224             </tr>
 225             <tr>
 226                 <td style="width: 104px">
 227                     <asp:FileUpload ID="FileUpload1" runat="server" Width="400px" />
 228                     </td>
 229                 <td style="width: 100px">
 230                     <asp:Button ID="bt_upload" runat="server" OnClick="bt_upload_Click" Text="上传"  OnClientClick="return Check_FileType()"/></td>
 231             </tr>
 232             <tr>
 233                 <td style="width: 104px; height: 21px;">
 234                     <asp:Label ID="lb_info" runat="server" ForeColor="Red" Width="183px"></asp:Label></td>
 235                 <td style="width: 100px; height: 21px">
 236                 </td>
 237             </tr>
 238         </table>
 239     
 240     </div>
 241     </form>
 242 </body>
 243 </html>
 244 说明:点击上传时先触发客户端事件Check_FileType;
 245 
 246 4.服务器端检查上传文件类型(以上传图片为例)
 247 
 248 效果图:
 249 
 250 
 251 后台代码:
 252 using System;
 253 using System.Data;
 254 using System.Configuration;
 255 using System.Collections;
 256 using System.Web;
 257 using System.Web.Security;
 258 using System.Web.UI;
 259 using System.Web.UI.WebControls;
 260 using System.Web.UI.WebControls.WebParts;
 261 using System.Web.UI.HtmlControls;
 262 
 263 public partial class _Default : System.Web.UI.Page
 264 {
 265     protected void Page_Load(object sender, EventArgs e)
 266     {
 267 
 268     }
 269     protected void bt_upload_Click(object sender, EventArgs e)
 270     {
 271         try
 272         {
 273             if (FileUpload1.PostedFile.FileName == "")
 274             {
 275                 this.lb_info.Text = "请选择文件!";
 276             }
 277             else
 278             {
 279                 string filepath = FileUpload1.PostedFile.FileName;
 280                 if (IsAllowedExtension(FileUpload1) == true)
 281                 {
 282 
 283                     string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);
 284                     string serverpath = Server.MapPath("images/") + filename;
 285                     FileUpload1.PostedFile.SaveAs(serverpath);
 286                     this.lb_info.Text = "上传成功!";
 287                 }
 288                 else 
 289                 {
 290                     this.lb_info.Text = "请上传图片";
 291                 }
 292             }
 293         }
 294         catch (Exception error)
 295         {
 296             this.lb_info.Text = "上传发生错误!原因:" + error.ToString();
 297         }
 298     }
 299    public static bool IsAllowedExtension(FileUpload hifile)
 300     {
 301         string strOldFilePath = "", strExtension = "";
 302         string[] arrExtension =   { ".gif", ".jpg", ".jpeg", ".bmp", ".png" };
 303         if (hifile.PostedFile.FileName != string.Empty)
 304         {
 305             strOldFilePath = hifile.PostedFile.FileName;
 306             strExtension = strOldFilePath.Substring(strOldFilePath.LastIndexOf("."));
 307             for (int i = 0; i < arrExtension.Length; i++)
 308             {
 309                 if (strExtension.Equals(arrExtension[i]))
 310                 {
 311                     return true;
 312                 }
 313             }
 314         }
 315         return false;
 316     }   
 317 
 318 }
 319 
 320 
 321  5.服务器端检查上传文件类型(可以检测真正文件名) 
 322 其实方法4并不好,因为用户可以把XXX.txt伪装为XXX.jpg。
 323 
 324 效果图:
 325 
 326 
 327 后台代码:
 328 using System;
 329 using System.Data;
 330 using System.Configuration;
 331 using System.Collections;
 332 using System.Web;
 333 using System.Web.Security;
 334 using System.Web.UI;
 335 using System.Web.UI.WebControls;
 336 using System.Web.UI.WebControls.WebParts;
 337 using System.Web.UI.HtmlControls;
 338 
 339 public partial class _Default : System.Web.UI.Page
 340 {
 341     //清清月儿 http://blog.csdn.Net/21as.Net
 342     protected void Page_Load(object sender, EventArgs e)
 343     {
 344 
 345     }
 346     protected void bt_upload_Click(object sender, EventArgs e)
 347     {
 348         try
 349         {
 350             if (FileUpload1.PostedFile.FileName == "")
 351             {
 352                 this.lb_info.Text = "请选择文件!";
 353             }
 354             else
 355             {
 356                 string filepath = FileUpload1.PostedFile.FileName;
 357                 if (IsAllowedExtension(FileUpload1) == true)
 358                 {
 359                     string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);
 360                     string serverpath = Server.MapPath("images/") + filename;
 361                     FileUpload1.PostedFile.SaveAs(serverpath);
 362                     this.lb_info.Text = "上传成功!";
 363                 }
 364                 else 
 365                 {
 366                     this.lb_info.Text = "请上传图片";
 367                 }
 368             }
 369         }
 370         catch (Exception error)
 371         {
 372             this.lb_info.Text = "上传发生错误!原因:" + error.ToString();
 373         }
 374     }
 375     public static bool IsAllowedExtension(FileUpload hifile)
 376     {
 377         System.IO.FileStream fs = new System.IO.FileStream(hifile.PostedFile.FileName, System.IO.FileMode.Open, System.IO.FileAccess.Read);
 378         System.IO.BinaryReader r = new System.IO.BinaryReader(fs);
 379         string fileclass = "";
 380         byte buffer;
 381         try
 382         {
 383             buffer = r.ReadByte();
 384             fileclass = buffer.ToString();
 385             buffer = r.ReadByte();
 386             fileclass += buffer.ToString();
 387 
 388         }
 389         catch 
 390         {
 391            
 392         }
 393         r.Close();
 394         fs.Close();
 395         if (fileclass == "255216" || fileclass == "7173")//说明255216是jpg;7173是gif;6677是BMP,13780是PNG;7790是exe,8297是rar
 396         {
 397             return true;
 398         }
 399         else 
 400         {
 401             return false;
 402         }
 403 
 404     }   
 405 
 406 }
 407 
 408 6.上传文件文件名唯一性处理(时间戳+SessionID)
 409 
 410 效果图:
 411 
 412 说明:年月日时分秒+临时session+原文件名 如果大家怕还会重复可以加GUID
 413 后台代码:
 414 
 415 
 416 try
 417         {
 418             if (FileUpload1.PostedFile.FileName == "")
 419             {
 420                 this.lb_info.Text = "请选择文件!";
 421             }
 422             else
 423             {
 424                 string filepath = FileUpload1.PostedFile.FileName;
 425                 string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);
 426                 string serverpath = Server.MapPath("images/") + System.DateTime.Now.ToString("yyy-MM-dd-hh-mm-ss") + Session.SessionID + filename;
 427                 FileUpload1.PostedFile.SaveAs(serverpath);
 428                 this.lb_info.Text = "上传成功!";
 429             }
 430         }
 431         catch (Exception error)
 432         {
 433             this.lb_info.Text = "上传发生错误!原因:" + error.ToString();
 434         }
 435 
 436 注:GUID的方法:Guid myGuid=Guid.NewGuid();
 437 
 438 7.上传图片生成等比例缩略图
 439 
 440 效果图:
 441 
 442 
 443 缩略图代码:
 444 ImageThumbnail.cs
 445 using System;
 446 using System.IO;
 447 using System.Drawing;
 448 using System.Drawing.Imaging;
 449 
 450 public class ImageThumbnail
 451 {
 452     public Image ResourceImage;
 453     private int ImageWidth;
 454     private int ImageHeight;
 455     public string ErrorMessage;
 456 
 457     public ImageThumbnail(string ImageFileName)
 458     {
 459         ResourceImage = Image.FromFile(ImageFileName);
 460         ErrorMessage = "";
 461     }
 462 
 463     public bool ThumbnailCallback()
 464     {
 465         return false;
 466     }
 467 
 468 
 469     // 方法1,按大小
 470     public bool ReducedImage(int Width, int Height, string targetFilePath)
 471     {
 472         try
 473         {
 474             Image ReducedImage;
 475             Image.GetThumbnailImageAbort callb = new Image.GetThumbnailImageAbort(ThumbnailCallback);
 476             ReducedImage = ResourceImage.GetThumbnailImage(Width, Height, callb, IntPtr.Zero);
 477             ReducedImage.Save(@targetFilePath, ImageFormat.Jpeg);
 478             ReducedImage.Dispose();
 479             return true;
 480         }
 481         catch (Exception e)
 482         {
 483             ErrorMessage = e.Message;
 484             return false;
 485         }
 486     }
 487 
 488 
 489     // 方法2,按百分比  缩小60% Percent为0.6 targetFilePath为目标路径
 490     public bool ReducedImage(double Percent, string targetFilePath)
 491     {
 492         try
 493         {
 494             Image ReducedImage;
 495             Image.GetThumbnailImageAbort callb = new Image.GetThumbnailImageAbort(ThumbnailCallback);
 496             ImageWidth = Convert.ToInt32(ResourceImage.Width * Percent);
 497             ImageHeight = (ResourceImage.Height)*ImageWidth/ ResourceImage.Width;//等比例缩放
 498             ReducedImage = ResourceImage.GetThumbnailImage(ImageWidth, ImageHeight, callb, IntPtr.Zero);
 499             ReducedImage.Save(@targetFilePath, ImageFormat.Jpeg);
 500             ReducedImage.Dispose();
 501             return true;
 502         }
 503         catch (Exception e)
 504         {
 505             ErrorMessage = e.Message;
 506             return false;
 507         }
 508     }
 509 
 510 
 511 }
 512 
 513 后台代码:
 514 using System;
 515 using System.Data;
 516 using System.Configuration;
 517 using System.Collections;
 518 using System.Web;
 519 using System.Web.Security;
 520 using System.Web.UI;
 521 using System.Web.UI.WebControls;
 522 using System.Web.UI.WebControls.WebParts;
 523 using System.Web.UI.HtmlControls;
 524 public partial class _Default : System.Web.UI.Page
 525 {
 526 
 527     protected void Page_Load(object sender, EventArgs e)
 528     {
 529 
 530     }
 531     protected void bt_upload_Click(object sender, EventArgs e)
 532     {
 533         try
 534         {
 535             if (FileUpload1.PostedFile.FileName == "")
 536             {
 537                 this.lb_info.Text = "请选择文件!";
 538             }
 539             else
 540             {
 541                 string filepath = FileUpload1.PostedFile.FileName;
 542                 string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);
 543                 string serverpath1 = Server.MapPath("images/") + filename;
 544                 string serverpath2 = Server.MapPath("images/") + System.DateTime.Now.ToString("yyy-MM-dd-hh-mm-ss") + Session.SessionID + filename;
 545                 FileUpload1.PostedFile.SaveAs(serverpath1);
 546                 ImageThumbnail img = new ImageThumbnail(filepath);
 547                 img.ReducedImage(0.4, serverpath2);//0.4表示缩小40%
 548                 this.lb_info.Text = "上传成功!";
 549             }
 550         }
 551         catch (Exception error)
 552         {
 553             this.lb_info.Text = "上传发生错误!原因:" + error.ToString();
 554         }
 555     }
 556 
 557 
 558 }
 559 
 560 8.上传图片加水印(文字水印,图片水印,文字+图片水印)
 561 
 562 效果图:
 563 原图
 564 
 565 水印
 566 
 567 给图片加水印以后(注意右上角+正下方)
 568 
 569 
 570 代码:
 571 DrawImg.cs  出自http://www.codeproject.com/csharp/watermark.asp
 572 using System;
 573 using System.Drawing;
 574 using System.Drawing.Imaging;
 575 using System.Drawing.Drawing2D;
 576 public class DrawImg
 577 {
 578  private string  WorkingDirectory = string.Empty ; //路径
 579  private string  ImageName = string.Empty;   //被处理的图片
 580  private string  ImageWater = string.Empty;  //水印图片
 581  private string  FontString = string.Empty;  //水印文字
 582  
 583 
 584  enum DealType{NONE,WaterImage,WaterFont,DoubleDo}; //枚举命令
 585 
 586  private DealType dealtype;
 587  
 588 
 589  public DrawImg()
 590  {}
 591 
 592  public string PublicWorkingDirectory
 593  {
 594   get
 595   {
 596    return WorkingDirectory;
 597   }
 598   set
 599   {
 600    WorkingDirectory = value;
 601   }
 602  }
 603 
 604  public string PublicImageName
 605  {
 606   get
 607   {
 608    return ImageName;
 609   }
 610   set
 611   {
 612    ImageName = value;
 613   }
 614  }
 615 
 616 
 617  public string PublicImageWater 
 618  {
 619   get
 620   {
 621    return ImageWater;
 622   }
 623   set  //设置了水印图片的话说明是要水印图片效果的
 624   {
 625    dealtype = DealType.WaterImage;
 626    ImageWater = value;
 627   }
 628  }
 629 
 630  public string PublicFontString
 631  {
 632   get
 633   {
 634    return FontString;
 635   }
 636   set //设置了水印文字的话说明是要水印文字效果的
 637   {
 638    dealtype = DealType.WaterFont;
 639    FontString = value;
 640   }
 641  }
 642 
 643  
 644 
 645  public void DealImage()
 646  {
 647   IsDouble();
 648 
 649   switch( dealtype )
 650   {
 651    case DealType.WaterFont: WriteFont(); break;
 652    case DealType.WaterImage: WriteImg(); break;
 653    case DealType.DoubleDo: WriteFontAndImg(); break;
 654   }
 655 
 656  }
 657 
 658  private void IsDouble()
 659  {
 660   if(ImageWater+""!="" && FontString+""!="")
 661   {
 662             dealtype = DealType.DoubleDo;
 663   }
 664  }
 665 
 666  private void WriteFont()
 667  {
 668   //set a working directory
 669   //string WorkingDirectory = @"C:\Watermark_src\WaterPic";
 670 
 671   //define a string of text to use as the Copyright message
 672   //string Copyright = "Copyright ?2002 - AP Photo/David Zalubowski";
 673 
 674   //create a image object containing the photograph to watermark
 675   Image imgPhoto = Image.FromFile(WorkingDirectory + ImageName);
 676   int phWidth = imgPhoto.Width;
 677   int phHeight = imgPhoto.Height;
 678 
 679   //create a Bitmap the Size of the original photograph
 680   Bitmap bmPhoto = new Bitmap(phWidth, phHeight, PixelFormat.Format24bppRgb);
 681 
 682   bmPhoto.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);
 683 
 684   //load the Bitmap into a Graphics object 
 685   Graphics grPhoto = Graphics.FromImage(bmPhoto);
 686 
 687   //------------------------------------------------------------
 688   //Step #1 - Insert Copyright message
 689   //------------------------------------------------------------
 690 
 691   //Set the rendering quality for this Graphics object
 692   grPhoto.SmoothingMode = SmoothingMode.AntiAlias;
 693 
 694   //Draws the photo Image object at original size to the graphics object.
 695   grPhoto.DrawImage(
 696    imgPhoto,                               // Photo Image object
 697    new Rectangle(0, 0, phWidth, phHeight), // Rectangle structure
 698    0,                                      // x-coordinate of the portion of the source image to draw. 
 699    0,                                      // y-coordinate of the portion of the source image to draw. 
 700    phWidth,                                // Width of the portion of the source image to draw. 
 701    phHeight,                               // Height of the portion of the source image to draw. 
 702    GraphicsUnit.Pixel);                    // Units of measure 
 703 
 704   //-------------------------------------------------------
 705   //to maximize the size of the Copyright message we will 
 706   //test multiple Font sizes to determine the largest posible 
 707   //font we can use for the width of the Photograph
 708   //define an array of point sizes you would like to consider as possiblities
 709   //-------------------------------------------------------
 710   int[] sizes = new int[]{16,14,12,10,8,6,4};
 711 
 712   Font crFont = null;
 713   SizeF crSize = new SizeF();
 714 
 715   //Loop through the defined sizes checking the length of the Copyright string
 716   //If its length in pixles is less then the image width choose this Font size.
 717   for (int i=0 ;i<7; i++)
 718   {
 719    //set a Font object to Arial (i)pt, Bold
 720    //crFont = new Font("arial", sizes[i], FontStyle.Bold);
 721 
 722    crFont = new Font("arial",sizes[i],FontStyle.Bold);
 723 
 724    //Measure the Copyright string in this Font
 725    crSize = grPhoto.MeasureString(FontString, crFont);
 726 
 727    if((ushort)crSize.Width < (ushort)phWidth)
 728     break;
 729   }
 730 
 731   //Since all photographs will have varying heights, determine a 
 732   //position 5% from the bottom of the image
 733   int yPixlesFromBottom = (int)(phHeight *.05);
 734 
 735   //Now that we have a point size use the Copyrights string height 
 736   //to determine a y-coordinate to draw the string of the photograph
 737   float yPosFromBottom = ((phHeight - yPixlesFromBottom)-(crSize.Height/2));
 738 
 739   //Determine its x-coordinate by calculating the center of the width of the image
 740   float xCenterOfImg = (phWidth/2);
 741 
 742   //Define the text layout by setting the text alignment to centered
 743   StringFormat StrFormat = new StringFormat();
 744   StrFormat.Alignment = StringAlignment.Center;
 745 
 746   //define a Brush which is semi trasparent black (Alpha set to 153)
 747   SolidBrush semiTransBrush2 = new SolidBrush(Color.FromArgb(153, 0, 0, 0));
 748 
 749   //Draw the Copyright string
 750   grPhoto.DrawString(FontString,                 //string of text
 751    crFont,                                   //font
 752    semiTransBrush2,                           //Brush
 753    new PointF(xCenterOfImg+1,yPosFromBottom+1),  //Position
 754    StrFormat);
 755 
 756   //define a Brush which is semi trasparent white (Alpha set to 153)
 757   SolidBrush semiTransBrush = new SolidBrush(Color.FromArgb(153, 255, 255, 255));
 758 
 759   //Draw the Copyright string a second time to create a shadow effect
 760   //Make sure to move this text 1 pixel to the right and down 1 pixel
 761   grPhoto.DrawString(FontString,                 //string of text
 762    crFont,         &nb, sp;                         //font
 763    semiTransBrush,                           //Brush
 764    new PointF(xCenterOfImg,yPosFromBottom),  //Position
 765    StrFormat);    
 766   
 767   imgPhoto = bmPhoto;
 768   grPhoto.Dispose();
 769 
 770   //save new image to file system.
 771   imgPhoto.Save(WorkingDirectory + ImageName + "_finally.jpg", ImageFormat.Jpeg);
 772   imgPhoto.Dispose();
 773   
 774   //Text alignment
 775  }
 776 
 777 
 778  private void WriteImg()
 779  {
 780   //set a working directory
 781   //string WorkingDirectory = @"C:\Watermark_src\WaterPic";
 782 
 783   //create a image object containing the photograph to watermark
 784   Image imgPhoto = Image.FromFile(WorkingDirectory + ImageName);
 785   int phWidth = imgPhoto.Width;
 786   int phHeight = imgPhoto.Height;
 787 
 788   //create a Bitmap the Size of the original photograph
 789   Bitmap bmPhoto = new Bitmap(phWidth, phHeight, PixelFormat.Format24bppRgb);
 790 
 791   bmPhoto.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);
 792 
 793   //load the Bitmap into a Graphics object 
 794   Graphics grPhoto = Graphics.FromImage(bmPhoto);
 795 
 796   //create a image object containing the watermark
 797   Image imgWatermark = new Bitmap(WorkingDirectory + ImageWater);
 798   int wmWidth = imgWatermark.Width;
 799   int wmHeight = imgWatermark.Height;
 800 
 801   //Set the rendering quality for this Graphics object
 802   grPhoto.SmoothingMode = SmoothingMode.AntiAlias;
 803 
 804   //Draws the photo Image object at original size to the graphics object.
 805   grPhoto.DrawImage(
 806    imgPhoto,                               // Photo Image object
 807    new Rectangle(0, 0, phWidth, phHeight), // Rectangle structure
 808    0,                                      // x-coordinate of the portion of the source image to draw. 
 809    0,                                      // y-coordinate of the portion of the source image to draw. 
 810    phWidth,                                // Width of the portion of the source image to draw. 
 811    phHeight,                               // Height of the portion of the source image to draw. 
 812    GraphicsUnit.Pixel);                    // Units of measure 
 813 
 814 
 815   //------------------------------------------------------------
 816   //Step #2 - Insert Watermark image
 817   //------------------------------------------------------------
 818 
 819   //Create a Bitmap based on the previously modified photograph Bitmap
 820   Bitmap bmWatermark = new Bitmap(bmPhoto);
 821   bmWatermark.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);
 822   //Load this Bitmap into a new Graphic Object
 823   Graphics grWatermark = Graphics.FromImage(bmWatermark);
 824 
 825   //To achieve a transulcent watermark we will apply (2) color 
 826   //manipulations by defineing a ImageAttributes object and 
 827   //seting (2) of its properties.
 828   ImageAttributes imageAttributes = new ImageAttributes();
 829 
 830   //The first step in manipulating the watermark image is to replace 
 831   //the background color with one that is trasparent (Alpha=0, R=0, G=0, B=0)
 832   //to do this we will use a Colormap and use this to define a RemapTable
 833   ColorMap colorMap = new ColorMap();
 834 
 835   //My watermark was defined with a background of 100% Green this will
 836   //be the color we search for and replace with transparency
 837   colorMap.OldColor = Color.FromArgb(255, 0, 255, 0);
 838   colorMap.NewColor = Color.FromArgb(0, 0, 0, 0); 
 839 
 840   ColorMap[] remapTable = {colorMap};
 841 
 842   imageAttributes.SetRemapTable(remapTable, ColorAdjustType.Bitmap);
 843 
 844   //The second color manipulation is used to change the opacity of the 
 845   //watermark.  This is done by applying a 5x5 matrix that contains the 
 846   //coordinates for the RGBA space.  By setting the 3rd row and 3rd column 
 847   //to 0.3f we achive a level of opacity
 848   float[][] colorMatrixElements = { 
 849            new float[] {1.0f,  0.0f,  0.0f,  0.0f, 0.0f},       
 850            new float[] {0.0f,  1.0f,  0.0f,  0.0f, 0.0f},        
 851            new float[] {0.0f,  0.0f,  1.0f,  0.0f, 0.0f},        
 852            new float[] {0.0f,  0.0f,  0.0f,  0.3f, 0.0f},        
 853            new float[] {0.0f,  0.0f,  0.0f,  0.0f, 1.0f}}; 
 854   ColorMatrix wmColorMatrix = new ColorMatrix(colorMatrixElements);
 855 
 856   imageAttributes.SetColorMatrix(wmColorMatrix, ColorMatrixFlag.Default,
 857    ColorAdjustType.Bitmap);
 858 
 859   //For this example we will place the watermark in the upper right
 860   //hand corner of the photograph. offset down 10 pixels and to the 
 861   //left 10 pixles
 862 
 863   int xPosOfWm = ((phWidth - wmWidth)-10);
 864   int yPosOfWm = 10;
 865 
 866   grWatermark.DrawImage(imgWatermark, 
 867    new Rectangle(xPosOfWm,yPosOfWm,wmWidth,wmHeight),  //Set the detination Position
 868    0,                  // x-coordinate of the portion of the source image to draw. 
 869    0,                  // y-coordinate of the portion of the source image to draw. 
 870    wmWidth,            // Watermark Width
 871    wmHeight,      // Watermark Height
 872    GraphicsUnit.Pixel, // Unit of measurment
 873    imageAttributes);   //ImageAttributes Object
 874 
 875   //Replace the original photgraphs bitmap with the new Bitmap
 876   imgPhoto = bmWatermark;
 877   grPhoto.Dispose();
 878   grWatermark.Dispose();
 879 
 880   //save new image to file system.
 881   imgPhoto.Save(WorkingDirectory + ImageName +"_finally.jpg", ImageFormat.Jpeg);
 882   imgPhoto.Dispose();
 883   imgWatermark.Dispose();
 884 
 885  }
 886 
 887 
 888  private void WriteFontAndImg()
 889  {  
 890   
 891   //create a image object containing the photograph to watermark
 892   Image imgPhoto = Image.FromFile(WorkingDirectory + ImageName);
 893   int phWidth = imgPhoto.Width;
 894   int phHeight = imgPhoto.Height;
 895 
 896   //create a Bitmap the Size of the original photograph
 897   Bitmap bmPhoto = new Bitmap(phWidth, phHeight, PixelFormat.Format24bppRgb);
 898 
 899   bmPhoto.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);
 900 
 901   //load the Bitmap into a Graphics object 
 902   Graphics grPhoto = Graphics.FromImage(bmPhoto);
 903 
 904   //create a image object containing the watermark
 905   Image imgWatermark = new Bitmap(WorkingDirectory + ImageWater);
 906   int wmWidth = imgWatermark.Width;
 907   int wmHeight = imgWatermark.Height;
 908 
 909   //------------------------------------------------------------
 910   //Step #1 - Insert Copyright message
 911   //------------------------------------------------------------
 912 
 913   //Set the rendering quality for this Graphics object
 914   grPhoto.SmoothingMode = SmoothingMode.AntiAlias;
 915 
 916   //Draws the photo Image object at original size to the graphics object.
 917   grPhoto.DrawImage(
 918    imgPhoto,                               // Photo Image object
 919    new Rectangle(0, 0, phWidth, phHeight), // Rectangle structure
 920    0,                                      // x-coordinate of the portion of the source image to draw. 
 921    0,                                      // y-coordinate of the portion of the source image to draw. 
 922    phWidth,                                // Width of the portion of the source image to draw. 
 923    phHeight,                               // Height of the portion of the source image to draw. 
 924    GraphicsUnit.Pixel);                    // Units of measure 
 925 
 926   //-------------------------------------------------------
 927   //to maximize the size of the Copyright message we will 
 928   //test multiple Font sizes to determine the largest posible 
 929   //font we can use for the width of the Photograph
 930   //define an array of point sizes you would like to consider as possiblities
 931   //-------------------------------------------------------
 932   int[] sizes = new int[]{16,14,12,10,8,6,4};
 933 
 934   Font crFont = null;
 935   SizeF crSize = new SizeF();
 936 
 937   //Loop through the defined sizes checking the length of the Copyright string
 938   //If its length in pixles is less then the image width choose this Font size.
 939   for (int i=0 ;i<7; i++)
 940   {
 941    //set a Font object to Arial (i)pt, Bold
 942    crFont = new Font("arial", sizes[i], FontStyle.Bold);
 943    //Measure the Copyright string in this Font
 944    crSize = grPhoto.MeasureString(FontString, crFont);
 945 
 946    if((ushort)crSize.Width < (ushort)phWidth)
 947     break;
 948   }
 949 
 950   //Since all photographs will have varying heights, determine a 
 951   //position 5% from the bottom of the image
 952   int yPixlesFromBottom = (int)(phHeight *.05);
 953 
 954   //Now that we have a point size use the Copyrights string height 
 955   //to determine a y-coordinate to draw the string of the photograph
 956   float yPosFromBottom = ((phHeight - yPixlesFromBottom)-(crSize.Height/2));
 957 
 958   //Determine its x-coordinate by calculating the center of the width of the image
 959   float xCenterOfImg = (phWidth/2);
 960 
 961   //Define the text layout by setting the text alignment to centered
 962   StringFormat StrFormat = new StringFormat();
 963   StrFormat.Alignment = StringAlignment.Center;
 964 
 965   //define a Brush which is semi trasparent black (Alpha set to 153)
 966   SolidBrush semiTransBrush2 = new SolidBrush(Color.FromArgb(153, 0, 0, 0));
 967 
 968   //Draw the Copyright string
 969   grPhoto.DrawString(FontString,                 //string of text
 970    crFont,                                   //font
 971    semiTransBrush2,                           //Brush
 972    new PointF(xCenterOfImg+1,yPosFromBottom+1),  //Position
 973    StrFormat);
 974 
 975   //define a Brush which is semi trasparent white (Alpha set to 153)
 976   SolidBrush semiTransBrush = new SolidBrush(Color.FromArgb(153, 255, 255, 255));
 977 
 978   //Draw the Copyright string a second time to create a shadow effect
 979   //Make sure to move this text 1 pixel to the right and down 1 pixel
 980   grPhoto.DrawString(FontString,                 //string of text
 981    crFont,                                   //font
 982    semiTransBrush,                           //Brush
 983    new PointF(xCenterOfImg,yPosFromBottom),  //Position
 984    StrFormat);                               //Text alignment
 985 
 986    
 987 
 988   //------------------------------------------------------------
 989   //Step #2 - Insert Watermark image
 990   //------------------------------------------------------------
 991 
 992   //Create a Bitmap based on the previously modified photograph Bitmap
 993   Bitmap bmWatermark = new Bitmap(bmPhoto);
 994   bmWatermark.SetResolution(imgPhoto.HorizontalResolution, imgPhoto.VerticalResolution);
 995   //Load this Bitmap into a new Graphic Object
 996   Graphics grWatermark = Graphics.FromImage(bmWatermark);
 997 
 998   //To achieve a transulcent watermark we will apply (2) color 
 999   //manipulations by defineing a ImageAttributes object and 
1000   //seting (2) of its properties.
1001   ImageAttributes imageAttributes = new ImageAttributes();
1002 
1003   //The first step in manipulating the watermark image is to replace 
1004   //the background color with one that is trasparent (Alpha=0, R=0, G=0, B=0)
1005   //to do this we will use a Colormap and use this to define a RemapTable
1006   ColorMap colorMap = new ColorMap();
1007 
1008   //My watermark was defined with a background of 100% Green this will
1009   //be the color we search for and replace with transparency
1010   colorMap.OldColor = Color.FromArgb(255, 0, 255, 0);
1011   colorMap.NewColor = Color.FromArgb(0, 0, 0, 0); 
1012 
1013   ColorMap[] remapTable = {colorMap};
1014 
1015   imageAttributes.SetRemapTable(remapTable, ColorAdjustType.Bitmap);
1016 
1017   //The second color manipulation is used to change the opacity of the 
1018   //watermark.  This is done by applying a 5x5 matrix that contains the 
1019   //coordinates for the RGBA space.  By setting the 3rd row and 3rd column 
1020   //to 0.3f we achive a level of opacity
1021   float[][] colorMatrixElements = { 
1022            new float[] {1.0f,  0.0f,  0.0f,  0.0f, 0.0f},       
1023            new float[] {0.0f,  1.0f,  0.0f,  0.0f, 0.0f},        
1024            new float[] {0.0f,  0.0f,  1.0f,  0.0f, 0.0f},        
1025            new float[] {0.0f,  0.0f,  0.0f,  0.3f, 0.0f},        
1026            new float[] {0.0f,  0.0f,  0.0f,  0.0f, 1.0f}}; 
1027   ColorMatrix wmColorMatrix = new ColorMatrix(colorMatrixElements);
1028 
1029   imageAttributes.SetColorMatrix(wmColorMatrix, ColorMatrixFlag.Default,
1030    ColorAdjustType.Bitmap);
1031 
1032   //For this example we will place the watermark in the upper right
1033   //hand corner of the photograph. offset down 10 pixels and to the 
1034   //left 10 pixles
1035 
1036   int xPosOfWm = ((phWidth - wmWidth)-10);
1037   int yPosOfWm = 10;
1038 
1039   grWatermark.DrawImage(imgWatermark, 
1040    new Rectangle(xPosOfWm,yPosOfWm,wmWidth,wmHeight),  //Set the detination Position
1041    0,                  // x-coordinate of the portion of the source image to draw. 
1042    0,                  // y-coordinate of the portion of the source image to draw. 
1043    wmWidth,            // Watermark Width
1044    wmHeight,      // Watermark Height
1045    GraphicsUnit.Pixel, // Unit of measurment
1046    imageAttributes);   //ImageAttributes Object
1047 
1048   //Replace the original photgraphs bitmap with the new Bitmap
1049   imgPhoto = bmWatermark;
1050   grPhoto.Dispose();
1051   grWatermark.Dispose();
1052 
1053   //save new image to file system.
1054   imgPhoto.Save(WorkingDirectory + ImageName +"_finally.jpg", ImageFormat.Jpeg);
1055   imgPhoto.Dispose();
1056   imgWatermark.Dispose();
1057 
1058         
1059  }
1060 }
1061 
1062 
1063  //水印图片加水印文字
1064 //   ReDrawImg img = new ReDrawImg();
1065 //   img .PublicWorkingDirectory = @"C:\Watermark_src\WaterPic\";
1066 //   img .PublicImageName = "watermark_photo.jpg";
1067 //   img .PublicImageWater = "watermark.bmp";
1068 //   img .PublicFontString = "清清月儿";
1069 //   img .DealImage(); 
1070   
1071    //水印文字
1072    ReDrawImg img = new ReDrawImg();
1073    img .PublicWorkingDirectory = @"C:\Watermark_src\WaterPic\";
1074    img .PublicImageName = "watermark_photo.jpg";   
1075    img .PublicFontString = @"清清月儿";
1076    img .DealImage();
1077  
1078 
1079    //水印图片
1080 //   ReDrawImg img = new ReDrawImg();
1081 //   img .PublicWorkingDirectory = @"C:\Watermark_src\WaterPic\";
1082 //   img .PublicImageName = "watermark_photo.jpg";
1083 //   img .PublicImageWater = "watermark.bmp";   
1084 //   img .DealImage(); 
1085   
1086  
1087 后台代码:
1088 
1089 using System;
1090 using System.Data;
1091 using System.Configuration;
1092 using System.Collections;
1093 using System.Web;
1094 using System.Web.Security;
1095 using System.Web.UI;
1096 using System.Web.UI.WebControls;
1097 using System.Web.UI.WebControls.WebParts;
1098 using System.Web.UI.HtmlControls;
1099 public partial class _Default : System.Web.UI.Page
1100 {
1101 
1102     protected void Page_Load(object sender, EventArgs e)
1103     {
1104 
1105     }
1106     protected void bt_upload_Click(object sender, EventArgs e)
1107     {
1108         try
1109         {
1110             if (FileUpload1.PostedFile.FileName == "")
1111             {
1112                 this.lb_info.Text = "请选择文件!";
1113             }
1114             else
1115             {
1116                 string filepath = FileUpload1.PostedFile.FileName;
1117                 string filename = filepath.Substring(filepath.LastIndexOf("\\") + 1);
1118                 string serverpath1 = Server.MapPath("images/") + filename;
1119                 //string serverpath2 = Server.MapPath("images/") + System.DateTime.Now.ToString("yyy-MM-dd-hh-mm-ss") + Session.SessionID + filename;
1120                 FileUpload1.PostedFile.SaveAs(serverpath1);
1121                 //ImageThumbnail img = new ImageThumbnail(filepath);
1122                 //img.ReducedImage(0.4, serverpath2);
1123                 DrawImg img = new DrawImg();
1124                 img.PublicWorkingDirectory = Server.MapPath("images/");
1125                 img.PublicImageName = filename;
1126                 img.PublicFontString = "http://blog.csdn.Net/21as.Net";
1127                 img.PublicImageWater = "yyy.jpg";
1128                 img.DealImage();
1129                 this.lb_info.Text = "上传成功!";
1130             }
1131         }
1132         catch (Exception error)
1133         {
1134             this.lb_info.Text = "上传发生错误!原因:" + error.ToString();
1135         }
1136     }
1137 }
1138 
posted @ 2017-02-10 15:43  清空回声  阅读(279)  评论(0编辑  收藏  举报