完整asp.net图形验证码程序

来源：互联网发布：软件看门狗的作用编辑：程序博客网时间：2024/05/22 06:30

前几天在网上找到的，我调试了一下，现在发布出来：

1、测试页面：Default.aspx

<%@ 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>ASP.NET验证码</title></head><body>    <form id="form1" runat="server">    <div>        请输入验证码：<input id="txtVI" type="text" name="view_id" runat="server" maxlength="5" size="5"/>     <asp:Image id="Image1" runat="server" ImageUrl="ValidateCode.aspx" ImageAlign="Middle" />        <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ErrorMessage="您没有输入验证码" ControlToValidate="txtVI"></asp:RequiredFieldValidator><br />        <asp:Button ID="Button1" runat="server" Text="提　交" OnClick="Button1_Click" /></div>    </form></body></html>

2、测试页面后台：Default.aspx.cs

using System;using System.Data;using System.Configuration;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 Button1_Click(object sender, EventArgs e)    {        string VNum;        VNum = Session["VNum"].ToString();        Session.Abandon();        ViewState["VNum"] = VNum;        if (txtVI.Value == ViewState["VNum"].ToString())        {            Response.Write("<script type="text/javascript">alert('验证码正确');</script>");            return;        }        else        {            Response.Write("<script type="text/javascript">alert('所填写的验证码不正确');</script>");            return;        }    }}

3、生成验证码页面:ValidateCode.aspx

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="ValidateCode.aspx.cs" Inherits="ValidateCode" >

4、生成验证码页面后台：

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;using System.Drawing; /* Copyright all(c) 2005 ZhongFeng, http://blog.csdn.net/SW515 */public partial class ValidateCode : System.Web.UI.Page{    private void Page_Load(object sender, System.EventArgs e)    {        this.CreateCheckCodeImage(GenerateCheckCode());    }     #region Web 窗体设计器生成的代码    override protected void OnInit(EventArgs e)    {        //        // CODEGEN: 该调用是 ASP.NET Web 窗体设计器所必需的。        //        InitializeComponent();        base.OnInit(e);    }     ///    /// 设计器支持所需的方法 - 不要使用代码编辑器修改    /// 此方法的内容。    ///    private void InitializeComponent()    {        this.Load += new System.EventHandler(this.Page_Load);    }    #endregion     private string GenerateCheckCode()    {        int number;        char code;        string checkCode = String.Empty;         System.Random random = new Random();         for (int i = 0; i < 5; i++)        {            number = random.Next();             if (number % 2 == 0)                code = (char)('0' + (char)(number % 10));            else                code = (char)('A' + (char)(number % 26));             checkCode += code.ToString();        }         Session["VNum"] = checkCode;         return checkCode;    }     private void CreateCheckCodeImage(string checkCode)    {        if (checkCode == null || checkCode.Trim() == String.Empty)            return;         System.Drawing.Bitmap image = new System.Drawing.Bitmap((int)Math.Ceiling((checkCode.Length * 12.5)), 22);        System.Drawing.Graphics g = Graphics.FromImage(image);         try        {            //生成随机生成器            Random random = new Random();             //清空图片背景色            g.Clear(Color.White);             //画图片的背景噪音线            for (int i = 0; i < 25; i++)            {                int x1 = random.Next(image.Width);                int x2 = random.Next(image.Width);                int y1 = random.Next(image.Height);                int y2 = random.Next(image.Height);                 g.DrawLine(new Pen(Color.Silver), x1, y1, x2, y2);            }             Font font = new System.Drawing.Font("Arial", 12, (System.Drawing.FontStyle.Bold | System.Drawing.FontStyle.Italic));            System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush(new Rectangle(0, 0, image.Width, image.Height), Color.Blue, Color.DarkRed, 1.2f, true);            g.DrawString(checkCode, font, brush, 2, 2);             //画图片的前景噪音点            for (int i = 0; i < 100; i++)            {                int x = random.Next(image.Width);                int y = random.Next(image.Height);                 image.SetPixel(x, y, Color.FromArgb(random.Next()));            }             //画图片的边框线            g.DrawRectangle(new Pen(Color.Silver), 0, 0, image.Width - 1, image.Height - 1);             System.IO.MemoryStream ms = new System.IO.MemoryStream();            image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);            Response.ClearContent();            Response.ContentType = "image/Gif";            Response.BinaryWrite(ms.ToArray());        }        finally        {            g.Dispose();            image.Dispose();        }    }}