用C#实现的验证码,与大家分享一下。。。
代码
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using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Drawing.Imaging;
using System.Web;
using System.Web.SessionState;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using System.IO;
namespace Shop
{
/// <summary>
/// Summary description for ValidateCode.
/// </summary>
public class ValidateCode : System.Web.UI.Page
{
/// <summary>
/// Validation Code generated fromt these charaters.
/// Note: l,L 1(number), o, O, 0(number) are removed
/// </summary>
private const string strValidateCodeBound = "abcdefghijkmnpqrstuvwxyzABCDEFGHIJKLMNPQRSTUVWXYZ23456789";
private static string[] Fonts = new string[] { "Helvetica",
"Geneva",
"sans-serif",
"Verdana",
"Times New Roman",
"Courier New",
"Arial"
};
#region Web Form Designer generated code
override protected void OnInit(EventArgs e)
{
//
// CODEGEN: This call is required by the ASP.NET Web Form Designer.
//
InitializeComponent();
base.OnInit(e);
}
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
private void InitializeComponent()
{
this.Load += new System.EventHandler(this.Page_Load);
}
#endregion
/// <summary>
/// event handler of page load
/// </summary>
private void Page_Load(object sender, System.EventArgs e)
{
if(!IsPostBack)
{
string str_ValidateCode = GetRandomString(6);
Session["ValidateCode"] = str_ValidateCode;
CreateImage(str_ValidateCode);
}
}
/// <summary>
/// Generate random string
/// </summary>
private string GetRandomString(int int_NumberLength)
{
string valString = string.Empty;
Random theRandomNumber = new Random((int)DateTime.Now.Ticks);
for (int int_index = 0; int_index < int_NumberLength; int_index++)
valString += strValidateCodeBound[theRandomNumber.Next(strValidateCodeBound.Length - 1)].ToString();
return valString;
}
/// <summary>
/// Generate random Color
/// </summary>
private Color GetRandomColor()
{
Random RandomNum_First = new Random((int)DateTime.Now.Ticks);
System.Threading.Thread.Sleep(RandomNum_First.Next(50));
Random RandomNum_Sencond = new Random((int)DateTime.Now.Ticks);
int int_Red = RandomNum_First.Next(256);
int int_Green = RandomNum_Sencond.Next(256);
int int_Blue = (int_Red + int_Green > 400) ? 0 : 400 - int_Red - int_Green;
int_Blue = (int_Blue > 255) ? 255 : int_Blue;
return Color.FromArgb(int_Red, int_Green, int_Blue);
}
/// <summary>
/// Create Validation Code Image
/// </summary>
private void CreateImage(string str_ValidateCode)
{
int int_ImageWidth = str_ValidateCode.Length * 22;
Random newRandom = new Random();
Bitmap theBitmap = new Bitmap(int_ImageWidth + 6 , 38);
Graphics theGraphics = Graphics.FromImage(theBitmap);
theGraphics.Clear(Color.White);
drawLine(theGraphics, theBitmap, newRandom);
theGraphics.DrawRectangle(new Pen(Color.LightGray, 1), 0, 0, theBitmap.Width - 1, theBitmap.Height -1 );
for (int int_index = 0; int_index < str_ValidateCode.Length; int_index++)
{
Matrix X = new Matrix();
X.Shear((float)newRandom.Next(0,300)/1000 - 0.25f, (float)newRandom.Next(0,100)/1000 - 0.05f);
theGraphics.Transform = X;
string str_char = str_ValidateCode.Substring(int_index, 1);
System.Drawing.Drawing2D.LinearGradientBrush newBrush = new System.Drawing.Drawing2D.LinearGradientBrush(new Rectangle(0, 0, theBitmap.Width, theBitmap.Height), Color.Blue, Color.DarkRed, 1.2f, true);
Point thePos = new Point(int_index * 21 + 1 + newRandom.Next(3), 1 + newRandom.Next(13));
Font theFont = new Font(Fonts[newRandom.Next(Fonts.Length -1)], newRandom.Next(14,18), FontStyle.Bold);
theGraphics.DrawString(str_char, theFont, newBrush, thePos);
}
drawPoint(theBitmap, newRandom);
MemoryStream ms = new MemoryStream();
theBitmap.Save(ms, ImageFormat.Png);
Response.ClearContent();
Response.ContentType = "image/Png";
Response.BinaryWrite(ms.ToArray());
theGraphics.Dispose();
theBitmap.Dispose();
Response.End();
}
/// <summary>
/// Draw Line for noise
/// </summary>
private void drawLine(Graphics gfc,Bitmap img, Random ran)
{
for (int i = 0; i < 10; i++)
{
int x1 = ran.Next(img.Width);
int y1 = ran.Next(img.Height);
int x2 = ran.Next(img.Width);
int y2 = ran.Next(img.Height);
gfc.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);
}
}
/// <summary>
/// Draw Point for noise
/// </summary>
private void drawPoint(Bitmap img, Random ran)
{
for (int i = 0; i < 30; i++)
{
int x = ran.Next(img.Width);
int y = ran.Next(img.Height);
img.SetPixel(x,y,Color.FromArgb(ran.Next()));
}
}
}
}