图片上传生成缩略图,并使用JQuery 实现鼠标移动到缩略图显示相应的大图的例子!

代码
<head runat="server">
<script type="text/javascript" src="script/jquery-1.3.2-vsdoc2.js"></script>

    
<link href="css/btn.css"  type="text/css" rel="Stylesheet" />
    
<title></title>
 
</head>
<body>
    
<form id="form1" runat="server">
    
<div>
        
<asp:FileUpload ID="FileUp" runat="server" CssClass="green1" />
        
<asp:Button ID="btnUp" runat="server" Text="上传" CssClass="green1" 
            onclick
="btnUp_Click" /><br />
        
<asp:Panel ID="Panel1" runat="server" >
       
</asp:Panel>
            
<asp:Image ID="ImShow" runat="server" ImageUrl="Images/3f76deb8623b1.jpg" Width="300px"  />
    
</div>
       
<script  type="text/javascript">
       



           var $ur 
= $("#ImShow").attr("src")


           $(
"image[src*='ico']").hover(function() {
               var $url 
=$(this).attr("src");
               $(
"#ImShow").attr("src", $url);
           }, function() {
               $(
"#ImShow").attr("src", $ur);
               
           });
        
    
     
    
</script>
    
</form>
</body>
</html>

 

代码
  public void QueryIco()
        {
          
            
string path = Server.MapPath("~/Images");
            DirectoryInfo dirinfo 
= new DirectoryInfo(Server.MapPath("~/ico"));
            FileInfo[] files
=dirinfo.GetFiles("*.jpg");
            
foreach (FileInfo file in files)
            {
               
                System.Web.UI.WebControls.Image im 
= new System.Web.UI.WebControls.Image();
                im.ImageUrl 
= "ico/"+file.Name;
                
this.Panel1.Controls.Add(im);
                
if (Panel1.Controls.Count % 4==0)
                {

                    
//使Panel中动态换行
                    this.Panel1.Controls.Add(new LiteralControl("<BR>"));
                }

                
            }

        }

        
protected void btnUp_Click(object sender, EventArgs e)
        {
            
//得到上传的路径
            string path = Server.MapPath("Images/");
           
//得到应用程序虚拟路径
           
// string path1 = ApplicationPath + "/Images/";
            string path2=Server.MapPath("~/ico/");
            
string type = System.IO.Path.GetExtension(FileUp.FileName).ToLower();
             
if(FileUp.HasFile)
             {
                 
if (type != ".jpg")
                {
                    Response.Write(
"<script>alert('文件类型不正确!')</script>");
                }
                
else
                {
                  
                        
string filename = this.FileUp.FileName;
                        
if (FileUp.PostedFile.ContentLength > 1024 *2*1024)
                        {
                            Response.Write(
"<script>alert('文件不能大于2M!')</script>");
                        }
                        
else
                        {
                            FileUp.SaveAs(path
+FileUp.FileName);
                            
this.ImShow.ImageUrl = "Images/" + FileUp.FileName;
                            MakeSmallImg(FileUp.PostedFile.InputStream, path2 
+ filename, 100200);

                         
//   Response.Write("<script>alert('"+path1+"!')</script>");
                            QueryIco();
                            
                        }
                
                }
             }
            
        }

        
// 按模版比例生成缩略图(以流的方式获取源文件)
        
//生成缩略图函数
        
//顺序参数:源图文件流、缩略图存放地址、模版宽、模版高
        
//注:缩略图大小控制在模版区域内
        public static void MakeSmallImg(System.IO.Stream fromFileStream, string fileSaveUrl, System.Double templateWidth, System.Double templateHeight)
        {
            
//从文件取得图片对象,并使用流中嵌入的颜色管理信息
            System.Drawing.Image myImage = System.Drawing.Image.FromStream(fromFileStream, true);
           

            
//缩略图宽、高
            System.Double newWidth = myImage.Width, newHeight = myImage.Height;
            
//宽大于模版的横图
            if (myImage.Width > myImage.Height || myImage.Width == myImage.Height)
            {
                
if (myImage.Width > templateWidth)
                {
                    
//宽按模版,高按比例缩放
                    newWidth = templateWidth;
                    newHeight 
= myImage.Height * (newWidth / myImage.Width);
                }
            }
            
//高大于模版的竖图
            else
            {
                
if (myImage.Height > templateHeight)
                {
                    
//高按模版,宽按比例缩放
                    newHeight = templateHeight;
                    newWidth 
= myImage.Width * (newHeight / myImage.Height);
                }
            }

            
//取得图片大小
            System.Drawing.Size mySize = new Size((int)newWidth, (int)newHeight);
            
//新建一个bmp图片
            System.Drawing.Image bitmap = new System.Drawing.Bitmap(mySize.Width, mySize.Height);
            
//新建一个画板
            
            System.Drawing.Graphics g 
= System.Drawing.Graphics.FromImage(bitmap);
            
//设置高质量插值法
            g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;
            
//设置高质量,低速度呈现平滑程度
            g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
            
//清空一下画布
            g.Clear(Color.White);
            
            
//在指定位置画图
            g.DrawImage(myImage, new System.Drawing.Rectangle(00, bitmap.Width, bitmap.Height),
            
new System.Drawing.Rectangle(00, myImage.Width, myImage.Height),
            System.Drawing.GraphicsUnit.Pixel);

            
///文字水印
            //System.Drawing.Graphics G=System.Drawing.Graphics.FromImage(bitmap);
            
//System.Drawing.Font f=new Font("宋体",10);
            
//System.Drawing.Brush b=new SolidBrush(Color.Black);
            
//G.DrawString("myohmine",f,b,10,10);
            
//G.Dispose(); 

            
///图片水印
            //System.Drawing.Image copyImage = System.Drawing.Image.FromFile(System.Web.HttpContext.Current.Server.MapPath("pic/1.gif"));
            
//Graphics a = Graphics.FromImage(bitmap);
            
//a.DrawImage(copyImage, new Rectangle(bitmap.Width-copyImage.Width,bitmap.Height-copyImage.Height,copyImage.Width, copyImage.Height),0,0, copyImage.Width, copyImage.Height, GraphicsUnit.Pixel); 

            
//copyImage.Dispose();
            
//a.Dispose();
            
//copyImage.Dispose(); 

            
//保存缩略图
            bitmap.Save(fileSaveUrl, System.Drawing.Imaging.ImageFormat.Jpeg);

            g.Dispose();
            myImage.Dispose();
            bitmap.Dispose();
        } 

 

posted @ 2010-05-06 17:25  雪莱·亨尼格  阅读(2693)  评论(1编辑  收藏  举报