c#随机数总结，汉字，英文，数字

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private static char[] constant = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z' };
     [WebMethod(Description="得到数字加英文的随机数，参数：随机数长度，返回值：一个字符串！")]
     public string pxkt_GetCharFont(int strLength)
     {
          System.Text.StringBuilder newRandom = new System.Text.StringBuilder(62);   
         Random rd = new Random();   
         for(int i=0;i<strLength;i++)   
         {   
           newRandom.Append(constant[rd.Next(62)]);   
         }   
         return    newRandom.ToString();   
     }

private static char[] englishchar = { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z' };
     [WebMethod(Description = "得到英文的随机数，参数：随机数长度，返回值：一个字符串！")]
     public string GetEnglishChar(int strLength)
     {
         System.Text.StringBuilder newRandom = new System.Text.StringBuilder(52);
         Random rd = new Random();
         for (int i = 0; i < strLength; i++)
         {
             newRandom.Append(englishchar[rd.Next(52)]);
         }
         return newRandom.ToString();  
     }

private static char[] numchar = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9' };
     [WebMethod(Description = "得到数字的随机数，参数：随机数长度，返回值：一个字符串！")]
     public string GetNumChar(int strLength)
     {
         System.Text.StringBuilder newRandom = new System.Text.StringBuilder(10);
         Random rd = new Random();
         for (int i = 0; i < strLength; i++)
         {
             newRandom.Append(numchar[rd.Next(10)]);
         }
         return newRandom.ToString();
     }

[WebMethod(Description = "得到中文的随机数，参数：随机数长度，返回值：一个字符串！")]
     public string GetChineseChar(int strLength)
     {
         System.Text.StringBuilder newRandom = new System.Text.StringBuilder();
         //获取GB2312编码页（表）
         System.Text.Encoding gb = System.Text.Encoding.GetEncoding("gb2312");
         //调用函数产生I个随机中文汉字编码
         object[] bytes = CreateRegionCode(strLength);     
         for (int i = 0; i < strLength; i++)
         {
             //根据汉字编码的字节数组解码出中文汉字
             string str = gb.GetString((byte[])Convert.ChangeType(bytes[i], typeof(byte[])));
             newRandom.Append(str);   
         }
         return newRandom.ToString();
     }

public static object[] CreateRegionCode(int strlength)
         {
             //定义一个字符串数组储存汉字编码的组成元素
             string[] rBase=new String [16]{"0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","f"};           
             Random rnd=new Random();       
             //定义一个object数组用来
             object[] bytes=new object[strlength];            
             for(int i=0;i<strlength;i++)
             {
                 //区位码第1位
                 int r1=rnd.Next(11,14);
                 string str_r1=rBase[r1].Trim();

//区位码第2位

//更换随机数发生器的种子避免产生重复值 
                 rnd=new Random(r1*unchecked((int)DateTime.Now.Ticks)+i);

int r2;
                 if (r1==13)
                 {
                     r2=rnd.Next(0,7);
                 }
                 else
                 {
                     r2=rnd.Next(0,16);
                 }
                 string str_r2=rBase[r2].Trim();

//区位码第3位
                 rnd=new Random(r2*unchecked((int)DateTime.Now.Ticks)+i);
                 int r3=rnd.Next(10,16);
                 string str_r3=rBase[r3].Trim();

//区位码第4位
                 rnd=new Random(r3*unchecked((int)DateTime.Now.Ticks)+i);
                 int r4;
                 if (r3==10)
                 {
                     r4=rnd.Next(1,16);
                 }
                 else if (r3==15)
                 {
                     r4=rnd.Next(0,15);
                 }
                 else
                 {
                     r4=rnd.Next(0,16);
                 }
                 string str_r4=rBase[r4].Trim();

//定义两个字节变量存储产生的随机汉字区位码
                 byte byte1=Convert.ToByte(str_r1 + str_r2,16);
                 byte byte2=Convert.ToByte(str_r3 + str_r4,16);
                 //将两个字节变量存储在字节数组中
                 byte[] str_r=new byte[]{byte1,byte2};

//将产生的一个汉字的字节数组放入object数组中
                 bytes.SetValue(str_r,i);                  
             } 
             return bytes; 
             }