当前文件： SiZeYunSuanYanZhengMa/ValidationCode/Image.aspx.cs[3K，2009-6-12 11:54:19]，打开代码结构图

		            
 1using System;
 2using System.Data;
 3using System.Configuration;
 4using System.Collections;
 5using System.Web;
 6using System.Web.Security;
 7using System.Web.UI;
 8using System.Web.UI.WebControls;
 9using System.Web.UI.WebControls.WebParts;
10using System.Web.UI.HtmlControls;
11
12using System.Drawing;
13using System.Drawing.Imaging;
14using System.Drawing.Drawing2D;
15
16namespace ValidationCode
17...{
18
19    public partial class Image : System.Web.UI.Page
20    ...{
21        protected void Page_Load(object sender, EventArgs e)
22        ...{
23            Random rd = new Random(); //创建随机数对象       
24
25            int Results = 0;
26            int Num1 = rd.Next(10); ;
27            int Num2 = rd.Next(10); ;
28            string Expressions = "";
29
30            int F=(rd.Next(4)+1);
31            switch (F)
32            ...{
33                case 1:
34                    Results = Num1 + Num2;
35                    Expressions = Num1 + "＋ " + Num2 + "＝ " + Results;
36                    break;
37                case 2:
38                    Results = Num1 - Num2;
39                    Expressions = Num1 + "－ " + Num2 + "＝ " + Results;
40                    break;
41                case 3:
42                    Results = Num1 * Num2;
43                    Expressions = Num1 + "×" + Num2 + "＝ " + Results;
44                    break;
45                case 4:
46                    if (Num2 > 0)
47                    ...{
48                        Results = Convert.ToInt16(Num1 / Num2);
49                        Expressions = Num1 + "整除 " + Num2 + "＝ " + Results;
50                    }
51                    else
52                    ...{
53                        Results = Num1;
54                        Expressions = Num1 + "整除 1＝ " + Results;
55                    }
56                    break;
57            }
58
59            //验证码值存放到Session中用来比较
60            Session["Code"] = Results.ToString();
61
62            //以下通过随机找一个现有图象产生一个画布Bitmap
63            //随机找个背景
64            string bgFilePath = Server.MapPath(".\\images\\bg" + new Random().Next(5) + ".jpg");
65            //string bgFilePath = Server.MapPath(".\\images\\bg10.jpg");
66
67
68            System.Drawing.Image imgObj = System.Drawing.Image.FromFile(bgFilePath);
69            //建立位图对象
70            Bitmap newBitmap = new Bitmap(imgObj, 290, 80);
71
72            //根据上面创建的位图对象创建绘图面
73            Graphics g = Graphics.FromImage(newBitmap);
74            //设置画笔颜色
75            SolidBrush brush = new SolidBrush(Color.Blue);
76
77            //定义一个含10种字体的数组
78            String[] fontFamily =...{ "Arial", "Verdana", "Comic Sans MS", "Impact", "Haettenschweiler", "Lucida Sans Unicode", "Garamond", "Courier New", "Book Antiqua", "Arial Narrow" };
79
80
81            //通过循环,绘制每个字符,
82            for (int a = 0; a < Expressions.Length; a++)
83            ...{
84                //字体随机,字号大小30,加粗 
85                Font textFont = new Font(fontFamily[rd.Next(9)],20, FontStyle.Bold);
86                //每次循环绘制一个字符,设置字体格式,画笔颜色,字符相对画布的X坐标,字符相对画布的Y坐标
87                g.DrawString(Expressions.Substring(a, 1), textFont, brush, 20 + a * 22, 25);
88            }
89
90            //保存画的图片到输出流中
91            newBitmap.Save(Response.OutputStream, ImageFormat.Gif);
92
93        }
94    }
95}
96