1
  2using System;
  3using System.Drawing;
  4using System.Drawing.Imaging;
  5using System.Web.UI;
  6using System.Drawing.Drawing2D;
  7using System.IO;
  8
  9 /**//// <summary>
 10 /// 生成验证码的类
 11 /// </summary>
 12 public class ValidateNumber
 13 ...{
 14  public ValidateNumber()
 15  ...{
 16  }
 17  /**//// <summary>
 18  /// 验证码的最大长度
 19  /// </summary>
 20  public int MaxLength
 21  ...{
 22   get...{return 10;}
 23  }
 24  /**//// <summary>
 25  /// 验证码的最小长度
 26  /// </summary>
 27  public int MinLength
 28  ...{
 29   get...{return 1;}
 30  }
 31  /**//// <summary>
 32  /// 生成验证码
 33  /// </summary>
 34  /// <param name="length">指定验证码的长度</param>
 35  /// <returns></returns>
 36  public string CreateValidateNumber(int length)
 37  ...{
 38   int[] randMembers=new int[length];
 39   int[] validateNums=new int[length];
 40   string validateNumberStr="";
 41   //生成起始序列值
 42   int seekSeek=unchecked((int)DateTime.Now.Ticks);
 43   Random seekRand=new Random(seekSeek);
 44   int beginSeek=(int)seekRand.Next(0,Int32.MaxValue-length*10000);
 45   int[] seeks=new int[length];
 46   for(int i=0;i<length;i++)
 47   ...{
 48    beginSeek+=10000;
 49    seeks[i]=beginSeek;
 50   }
 51   //生成随机数字
 52   for(int i=0;i<length;i++)
 53   ...{
 54    Random rand=new Random(seeks[i]);
 55    int pownum=1*(int)Math.Pow(10,length);
 56    randMembers[i]=rand.Next(pownum,Int32.MaxValue);
 57   }
 58   //抽取随机数字
 59   for(int i=0;i<length;i++)
 60   ...{
 61    string numStr=randMembers[i].ToString();
 62    int numLength=numStr.Length;
 63    Random rand=new Random();
 64    int numPosition=rand.Next(0,numLength-1);
 65    validateNums[i]=Int32.Parse(numStr.Substring(numPosition,1));
 66   }
 67   //生成验证码
 68   for(int i=0;i<length;i++)
 69   ...{
 70    validateNumberStr+=validateNums[i].ToString();
 71   }
 72   return validateNumberStr;
 73  }
 74  /**//// <summary>
 75  /// 创建验证码的图片
 76  /// </summary>
 77  /// <param name="containsPage">要输出到的page对象</param>
 78  /// <param name="validateNum">验证码</param>
 79  public void CreateValidateGraphic(Page containsPage,string validateNum)
 80  ...{
 81   Bitmap image=new Bitmap((int)Math.Ceiling(validateNum.Length*12.5),22);
 82   Graphics g=Graphics.FromImage(image);
 83   try
 84   ...{
 85    //生成随机生成器
 86    Random random=new Random();
 87    //清空图片背景色
 88    g.Clear(Color.White);
 89    //画图片的干扰线
 90    for(int i=0;i<25;i++)
 91    ...{
 92     int x1=random.Next(image.Width);
 93     int x2=random.Next(image.Width);
 94     int y1=random.Next(image.Height);
 95     int y2=random.Next(image.Height);
 96     g.DrawLine(new Pen(Color.Silver),x1,y1,x2,y2);
 97    }
 98    Font font=new Font("Arial",12,(FontStyle.Bold|FontStyle.Italic));
 99    LinearGradientBrush brush=new LinearGradientBrush(new Rectangle(0,0,image.Width,image.Height),
100     Color.Blue,Color.DarkRed,1.2f,true);
101    g.DrawString(validateNum,font,brush,3,2);
102    //画图片的前景干扰点
103    for(int i=0;i<100;i++)
104    ...{
105     int x=random.Next(image.Width);
106     int y=random.Next(image.Height);
107     image.SetPixel(x,y,Color.FromArgb(random.Next()));
108    }
109    //画图片的边框线
110    g.DrawRectangle(new Pen(Color.Silver),0,0,image.Width-1,image.Height-1);
111    //保存图片数据
112    MemoryStream stream=new MemoryStream();
113    image.Save(stream,ImageFormat.Jpeg);
114    //输出图片
115    containsPage.Response.Clear();
116    containsPage.Response.ContentType="image/jpeg";
117    containsPage.Response.BinaryWrite(stream.ToArray());
118   }
119   finally
120   ...{
121    g.Dispose();
122    image.Dispose();
123   }
124  }
125  /**//// <summary>
126  /// 得到验证码图片的长度
127  /// </summary>
128  /// <param name="validateNumLength">验证码的长度</param>
129  /// <returns></returns>
130  public static int GetImageWidth(int validateNumLength)
131  ...{
132   return (int)(validateNumLength*12.5);
133  }
134  /**//// <summary>
135  /// 得到验证码的高度
136  /// </summary>
137  /// <returns></returns>
138  public static double GetImageHeight()
139  ...{
140   return 22.5;
141  }
142}
143
144