C#验证码使用

1、C#创建验证码

1.1 创建获取验证码页面（ValidateCode.aspx）

 

[html] view plaincopyprint?
  1. <html xmlns="http://www.w3.org/1999/xhtml">  
  2. <head runat="server">  
  3.     <title>获取验证码</title>  
  4. </head>  
  5. <body>  
  6.     <form id="form1" runat="server">  
  7.         <div>获取验证码</div>  
  8.     </form>  
  9. </body>  
  10. </html>  
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>获取验证码</title>
</head>
<body>
    <form id="form1" runat="server">
        <div>获取验证码</div>
    </form>
</body>
</html>


1.2 编写获取验证码代码（ValidateCode.aspx.cs）

 

 

[csharp] view plaincopyprint?
  1. /// <summary>   
  2. /// 验证码类型(0-字母数字混合,1-数字,2-字母)   
  3. /// </summary>   
  4. private string validateCodeType = "0";  
  5. /// <summary>   
  6. /// 验证码字符个数   
  7. /// </summary>   
  8. private int validateCodeCount = 4;  
  9. /// <summary>   
  10. /// 验证码的字符集，去掉了一些容易混淆的字符   
  11. /// </summary>   
  12. char[] character = { '2', '3', '4', '5', '6', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'J', 'K', 'L', 'M', 'N', 'P', 'R', 'S', 'T', 'W', 'X', 'Y' };  
  13.   
  14. protected void Page_Load(object sender, EventArgs e)  
  15. {  
  16.     //取消缓存   
  17.     Response.BufferOutput = true;  
  18.     Response.Cache.SetExpires(DateTime.Now.AddMilliseconds(-1));  
  19.     Response.Cache.SetCacheability(System.Web.HttpCacheability.NoCache);  
  20.     Response.AppendHeader("Pragma", "No-Cache");  
  21.     //获取设置参数   
  22.     if (!string.IsNullOrEmpty(Request.QueryString["validateCodeType"]))  
  23.     {  
  24.         validateCodeType = Request.QueryString["validateCodeType"];  
  25.     }  
  26.     if (!string.IsNullOrEmpty(Request.QueryString["validateCodeCount"]))  
  27.     {  
  28.         int.TryParse(Request.QueryString["validateCodeCount"], out validateCodeCount);  
  29.     }  
  30.     //生成验证码   
  31.     this.CreateCheckCodeImage(GenerateCheckCode());  
  32. }  
  33.   
  34. private string GenerateCheckCode()  
  35. {  
  36.     char code ;  
  37.     string checkCode = String.Empty;  
  38.     System.Random random = new Random();  
  39.   
  40.     for (int i = 0; i < validateCodeCount; i++)  
  41.     {  
  42.         code = character[random.Next(character.Length)];  
  43.   
  44.         // 要求全为数字或字母   
  45.         if (validateCodeType == "1")  
  46.         {  
  47.             if ((int)code < 48 || (int)code > 57)  
  48.             {  
  49.                 i--;  
  50.                 continue;  
  51.             }  
  52.         }  
  53.         else if (validateCodeType == "2")  
  54.         {  
  55.             if ((int)code < 65 || (int)code > 90)  
  56.             {  
  57.                 i--;  
  58.                 continue;  
  59.             }  
  60.         }  
  61.         checkCode += code;  
  62.     }  
  63.   
  64.     Response.Cookies.Add(new System.Web.HttpCookie("CheckCode", checkCode));  
  65.     this.Session["CheckCode"] = checkCode;  
  66.     return checkCode;  
  67. }  
  68.   
  69. private void CreateCheckCodeImage(string checkCode)  
  70. {  
  71.     if (checkCode == null || checkCode.Trim() == String.Empty)  
  72.         return;  
  73.   
  74.     System.Drawing.Bitmap image = new System.Drawing.Bitmap((int)Math.Ceiling((checkCode.Length*15.0+40)), 23);  
  75.     System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(image);  
  76.   
  77.     try  
  78.     {  
  79.         //生成随机生成器   
  80.         Random random = new Random();  
  81.   
  82.         //清空图片背景色   
  83.         g.Clear(System.Drawing.Color.White);  
  84.   
  85.         //画图片的背景噪音线   
  86.         for (int i = 0; i < 25; i++)  
  87.         {  
  88.             int x1 = random.Next(image.Width);  
  89.             int x2 = random.Next(image.Width);  
  90.             int y1 = random.Next(image.Height);  
  91.             int y2 = random.Next(image.Height);  
  92.   
  93.             g.DrawLine(new System.Drawing.Pen(System.Drawing.Color.Silver), x1, y1, x2, y2);  
  94.         }  
  95.   
  96.         System.Drawing.Font font = new System.Drawing.Font("Arial", 14, (System.Drawing.FontStyle.Bold | System.Drawing.FontStyle.Italic));  
  97.         System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush(new System.Drawing.Rectangle(0, 0, image.Width, image.Height), System.Drawing.Color.Blue, System.Drawing.Color.DarkRed, 1.2f, true);  
  98.   
  99.         int cySpace = 16;  
  100.         for (int i = 0; i < validateCodeCount; i++)  
  101.         {  
  102.             g.DrawString(checkCode.Substring(i, 1), font, brush, (i + 1) * cySpace, 1);  
  103.         }  
  104.   
  105.         //画图片的前景噪音点   
  106.         for (int i = 0; i < 100; i++)  
  107.         {  
  108.             int x = random.Next(image.Width);  
  109.             int y = random.Next(image.Height);  
  110.   
  111.             image.SetPixel(x, y, System.Drawing.Color.FromArgb(random.Next()));  
  112.         }  
  113.   
  114.         //画图片的边框线   
  115.         g.DrawRectangle(new System.Drawing.Pen(System.Drawing.Color.Silver), 0, 0, image.Width - 1, image.Height - 1);  
  116.   
  117.         System.IO.MemoryStream ms = new System.IO.MemoryStream();  
  118.         image.Save(ms, System.Drawing.Imaging.ImageFormat.Gif);  
  119.         Response.ClearContent();  
  120.         Response.ContentType = "image/Gif";  
  121.         Response.BinaryWrite(ms.ToArray());  
  122.     }  
  123.     finally  
  124.     {  
  125.         g.Dispose();  
  126.         image.Dispose();  
  127.     }  
  128. }  
/// <summary>
/// 验证码类型(0-字母数字混合,1-数字,2-字母)
/// </summary>
private string validateCodeType = "0";
/// <summary>
/// 验证码字符个数
/// </summary>
private int validateCodeCount = 4;
/// <summary>
/// 验证码的字符集，去掉了一些容易混淆的字符
/// </summary>
char[] character = { '2', '3', '4', '5', '6', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'J', 'K', 'L', 'M', 'N', 'P', 'R', 'S', 'T', 'W', 'X', 'Y' };

protected void Page_Load(object sender, EventArgs e)
{
    //取消缓存
    Response.BufferOutput = true;
    Response.Cache.SetExpires(DateTime.Now.AddMilliseconds(-1));
    Response.Cache.SetCacheability(System.Web.HttpCacheability.NoCache);
    Response.AppendHeader("Pragma", "No-Cache");
    //获取设置参数
    if (!string.IsNullOrEmpty(Request.QueryString["validateCodeType"]))
    {
        validateCodeType = Request.QueryString["validateCodeType"];
    }
    if (!string.IsNullOrEmpty(Request.QueryString["validateCodeCount"]))
    {
        int.TryParse(Request.QueryString["validateCodeCount"], out validateCodeCount);
    }
    //生成验证码
    this.CreateCheckCodeImage(GenerateCheckCode());
}

private string GenerateCheckCode()
{
    char code ;
    string checkCode = String.Empty;
    System.Random random = new Random();

    for (int i = 0; i < validateCodeCount; i++)
    {
        code = character[random.Next(character.Length)];

        // 要求全为数字或字母
        if (validateCodeType == "1")
        {
            if ((int)code < 48 || (int)code > 57)
            {
                i--;
                continue;
            }
        }
        else if (validateCodeType == "2")
        {
            if ((int)code < 65 || (int)code > 90)
            {
                i--;
                continue;
            }
        }
        checkCode += code;
    }

    Response.Cookies.Add(new System.Web.HttpCookie("CheckCode", checkCode));
    this.Session["CheckCode"] = 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*15.0+40)), 23);
    System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(image);

    try
    {
        //生成随机生成器
        Random random = new Random();

        //清空图片背景色
        g.Clear(System.Drawing.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 System.Drawing.Pen(System.Drawing.Color.Silver), x1, y1, x2, y2);
        }

        System.Drawing.Font font = new System.Drawing.Font("Arial", 14, (System.Drawing.FontStyle.Bold | System.Drawing.FontStyle.Italic));
        System.Drawing.Drawing2D.LinearGradientBrush brush = new System.Drawing.Drawing2D.LinearGradientBrush(new System.Drawing.Rectangle(0, 0, image.Width, image.Height), System.Drawing.Color.Blue, System.Drawing.Color.DarkRed, 1.2f, true);

        int cySpace = 16;
        for (int i = 0; i < validateCodeCount; i++)
        {
            g.DrawString(checkCode.Substring(i, 1), font, brush, (i + 1) * cySpace, 1);
        }

        //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, System.Drawing.Color.FromArgb(random.Next()));
        }

        //画图片的边框线
        g.DrawRectangle(new System.Drawing.Pen(System.Drawing.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();
    }
}

2、验证码的使用

 

2.1 验证码的前段显示代码

 

[html] view plaincopyprint?
  1. <img src="/ValidateCode.aspx?ValidateCodeType=1&0.011150883024061309" onclick="this.src='/ValidateCode.aspx?ValidateCodeType=1&'+Math.random();" id="imgValidateCode" alt="点击刷新验证码" title="点击刷新验证码" style="cursor: pointer;">  
<img src="/ValidateCode.aspx?ValidateCodeType=1&0.011150883024061309" onclick="this.src='/ValidateCode.aspx?ValidateCodeType=1&'+Math.random();" id="imgValidateCode" alt="点击刷新验证码" title="点击刷新验证码" style="cursor: pointer;">

 

2.2 创建验证码测试页面（ValidateTest.aspx）

[html] view plaincopyprint?
  1. <html xmlns="http://www.w3.org/1999/xhtml">  
  2. <head runat="server">  
  3.     <title>验证码测试</title>  
  4. </head>  
  5. <body>  
  6.     <form id="form1" runat="server">  
  7.     <div>  
  8.         <input runat="server" id="txtValidate" />  
  9.         <img src="/ValidateCode.aspx?ValidateCodeType=1&0.011150883024061309" onclick="this.src='/ValidateCode.aspx?ValidateCodeType=1&'+Math.random();" id="imgValidateCode" alt="点击刷新验证码" title="点击刷新验证码" style="cursor: pointer;">  
  10.         <asp:Button runat="server" id="btnVal" Text="提交" onclick="btnVal_Click"  />  
  11.     </div>  
  12.     </form>  
  13. </body>  
  14. </html>  
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>验证码测试</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
        <input runat="server" id="txtValidate" />
        <img src="/ValidateCode.aspx?ValidateCodeType=1&0.011150883024061309" onclick="this.src='/ValidateCode.aspx?ValidateCodeType=1&'+Math.random();" id="imgValidateCode" alt="点击刷新验证码" title="点击刷新验证码" style="cursor: pointer;">
        <asp:Button runat="server" id="btnVal" Text="提交" onclick="btnVal_Click"  />
    </div>
    </form>
</body>
</html>

2.3 编写验证码测试的提交代码（ValidateTest.aspx.cs）

 

 

[csharp] view plaincopyprint?
  1. protected void btnVal_Click(object sender, EventArgs e)  
  2. {  
  3.     bool result = false;   //验证结果   
  4.     string userCode = this.txtValidate.Value; //获取用户输入的验证码   
  5.     if (String.IsNullOrEmpty(userCode))  
  6.     {   
  7.         //请输入验证码   
  8.         return;  
  9.     }  
  10.   
  11.     string validCode = this.Session["CheckCode"] as String;  //获取系统生成的验证码   
  12.     if (!string.IsNullOrEmpty(validCode))  
  13.     {  
  14.         if (userCode.ToLower() == validCode.ToLower())  
  15.         {  
  16.             //验证成功   
  17.             result = true;  
  18.         }  
  19.         else  
  20.         {  
  21.             //验证失败   
  22.             result = false;  
  23.         }  
  24.     }  
  25. }  
posted @ 2013-07-22 21:41  youhumian  阅读(430)  评论(0)  编辑  收藏  举报