/// <summary>
2 /// ValidaterCodeHandler 的摘要说明(此项是建立一般处理数据)
3 /// </summary>
4 public class ValidaterCodeHandler : IHttpHandler,IRequiresSessionState
5 {
6 public void ProcessRequest(HttpContext context)
7 {
8 string chechCode = GenCode1(5);
9 // 创建用来绘制验证码的位图
10 System.Drawing.Bitmap image = new System.Drawing.Bitmap(100,23);
11 //从位图中获取对应的绘图类对象
12 Graphics g = Graphics.FromImage(image);
13 // 将产生的验证码先存到Session中，方便与用户填写的验证码进行比较
14 context.Session["code"] = chechCode;
15 try
16 {
17 // 生成随机生成器
18 Random random = new Random();
19 // 清空图片背景色
20 g.Clear(Color.White);
21 // 画图片的背景噪音线
22 for (int i = 0; i < 25; i++)
23 {
24 int x1 = random.Next(image.Width);
25 int x2 = random.Next(image.Width);
26 int y2 = random.Next(image.Height);
27 int y1 = random.Next(image.Height);
28 g.DrawLine(new Pen(Color.Silver),x1,y1,x2,y2);
29 }
30
31 Font font = new Font("Arial",12,System.Drawing.FontStyle.Bold);
32 LinearGradientBrush brush = new LinearGradientBrush(new Rectangle(0,0,image.Width,image.Height),Color.Blue,Color.DarkRed,1.2F,true);
33 g.DrawString(chechCode,font,brush,2,2);
34 // 画图片的前景噪音点
35 g.DrawRectangle(new Pen(Color.Silver),0,0,image.Width - 1,image.Height - 1);
36 MemoryStream ms = new MemoryStream();
37 image.Save(ms,ImageFormat.Gif);
38 context.Response.ClearContent();
39 context.Response.ContentType = "image/Gif";
40 context.Response.BinaryWrite(ms.ToArray());
41 }
42 finally
43 {
44 g.Dispose();
45 image.Dispose();
46 }
47 }
48
49 public bool IsReusable
50 {
51 get
52 {
53 return false;
54 }
55 }
56
57 /// <summary>
58 /// 产生随机数、字母字符串
59 /// </summary>
60 /// <param name="num">随机出几个字符</param>
61 /// <returns>随机出的字符</returns>
62 private string GenCode1(int num)
63 {
64 string str = "0123456789qwertyuioplkjhgfdsazxcvbnm";
65 string code = "";
66 Random rd = new Random();
67 for (int i = 0; i < num; i++)
68 {
69 code += str.Substring(rd.Next(0,str.Length),1);
70 }
71 return code;
72 }
73
74 /// <summary>
75 /// 产生汉字
76 /// </summary>
77 /// <param name="num">随机出几个字符</param>
78 /// <returns>随机出的字符串</returns>
79 private string GenCode2(int num)
80 {
81 string str = "啥打法是否客户看大能打开富室发高精度将对方开始";
82 string code = "";
83 Random rd = new Random();
84 for (int i = 0; i < num; i++)
85 {
86 code += str.Substring(rd.Next(0,str.Length),1);
87 }
88
89 return code;
90 }
91 }
92
93
94
95
96 // 页面代码
97 <head runat="server">
98 <title></title>
99 <script type = "text/javascript">
100 function fresh() {
101 document.getElementById("code").src = "ValidaterCodeHandler.ashx?time = " + new Date();
102 }
103 </script>
104 </head>
105 <body>
106 <form id="form1" runat="server">
107 <div>
108 登录页面
109 <br />
110 <br />
111 用户名：<asp:TextBox ID="txtUserName" runat="server"></asp:TextBox>
112 <br />
113 <br />
114 密 码：<asp:TextBox ID="txtPwd" runat="server" TextMode="Password"></asp:TextBox>
115 <br />
116 <br />
117 验证码：<asp:TextBox ID="txtValidaterCode" runat="server"></asp:TextBox>
118 <img id = "code" src = "ValidaterCodeHandler.ashx" onclick = "fresh()" />
119 <a href = "javascript:fresh()">看不清？换一个</a>
120 <br />
121 <br />
122 <asp:Button ID="btnLogin" runat="server" Text="登录" onclick="btnLogin_Click" />
123
124 </div>
125 </form>
126 </body>
