(C#)生成指定长度的随机字符串的通用方法

.NET(C#)生成指定长度的随机字符串的通用方法，此方法可以指定字符串的长度，是否包含数字，是否包含符号，是否包含小写字母，是否包含大写字母等，

源码：

  #region 生成指定长度的随机字符串
         /// <summary>
         /// 生成指定长度的随机字符串
         /// </summary>
         /// <param name="intLength">随机字符串长度</param>
         /// <param name="booNumber">生成的字符串中是否包含数字</param>
         /// <param name="booSign">生成的字符串中是否包含符号</param>
         /// <param name="booSmallword">生成的字符串中是否包含小写字母</param>
         /// <param name="booBigword">生成的字符串中是否包含大写字母</param>
         /// <returns></returns>
         public string GetRandomizer(int intLength, bool booNumber, bool booSign, bool booSmallword, bool booBigword)
         {
             //定义
             Random ranA = new Random();
             int intResultRound = ;
             int intA = ;
             string strB = "";

             while (intResultRound < intLength)
             {
                 //生成随机数A，表示生成类型
                 //1=数字，2=符号，3=小写字母，4=大写字母  

                 intA = ranA.Next(, );

                 //如果随机数A=1，则运行生成数字
                 //生成随机数A，范围在0-10
                 //把随机数A，转成字符
                 //生成完，位数+1，字符串累加，结束本次循环  

                 if (intA ==  && booNumber)
                 {
                     intA = ranA.Next(, );
                     strB = intA.ToString() + strB;
                     intResultRound = intResultRound + ;
                     continue;
                 }

                 //如果随机数A=2，则运行生成符号
                 //生成随机数A，表示生成值域
                 //1：33-47值域，2：58-64值域，3：91-96值域，4：123-126值域  

                 if (intA ==  && booSign == true)
                 {
                     intA = ranA.Next(, );

                     //如果A=1
                     //生成随机数A，33-47的Ascii码
                     //把随机数A，转成字符
                     //生成完，位数+1，字符串累加，结束本次循环  

                     if (intA == )
                     {
                         intA = ranA.Next(, );
                         strB = ((char)intA).ToString() + strB;
                         intResultRound = intResultRound + ;
                         continue;
                     }

                     //如果A=2
                     //生成随机数A，58-64的Ascii码
                     //把随机数A，转成字符
                     //生成完，位数+1，字符串累加，结束本次循环  

                     if (intA == )
                     {
                         intA = ranA.Next(, );
                         strB = ((char)intA).ToString() + strB;
                         intResultRound = intResultRound + ;
                         continue;
                     }

                     //如果A=3
                     //生成随机数A，91-96的Ascii码
                     //把随机数A，转成字符
                     //生成完，位数+1，字符串累加，结束本次循环  

                     if (intA == )
                     {
                         intA = ranA.Next(, );
                         strB = ((char)intA).ToString() + strB;
                         intResultRound = intResultRound + ;
                         continue;
                     }

                     //如果A=4
                     //生成随机数A，123-126的Ascii码
                     //把随机数A，转成字符
                     //生成完，位数+1，字符串累加，结束本次循环  

                     if (intA == )
                     {
                         intA = ranA.Next(, );
                         strB = ((char)intA).ToString() + strB;
                         intResultRound = intResultRound + ;
                         continue;
                     }

                 }

                 //如果随机数A=3，则运行生成小写字母
                 //生成随机数A，范围在97-122
                 //把随机数A，转成字符
                 //生成完，位数+1，字符串累加，结束本次循环  

                 if (intA ==  && booSmallword == true)
                 {
                     intA = ranA.Next(, );
                     strB = ((char)intA).ToString() + strB;
                     intResultRound = intResultRound + ;
                     continue;
                 }

                 //如果随机数A=4，则运行生成大写字母
                 //生成随机数A，范围在65-90
                 //把随机数A，转成字符
                 //生成完，位数+1，字符串累加，结束本次循环  

                 if (intA ==  && booBigword == true)
                 {
                     intA = ranA.Next(, );
                     strB = ((char)intA).ToString() + strB;
                     intResultRound = intResultRound + ;
                     continue;
                 }
             }
             return strB;

         }
         #endregion

读取数据：

  private void button1_Click(object sender, EventArgs e)
         {
             foreach (var file in Directory.GetFiles("E:\\renew", "*.txt").Where(t => t.ToLower().EndsWith(".txt")).ToList())
             {
                 using (StreamReader reader = new StreamReader(file, Encoding.UTF8))
                 {
                     string strLine = string.Empty;
                     while ((strLine = reader.ReadLine()) != null)
                     {
                         renewModel.Content = strLine;
                         renewBLL.Add(renewModel);
                     }
                 }
             }
         }

写入数据：

   private void button2_Click(object sender, EventArgs e)
         {
             StreamWriter sw = new StreamWriter(@"E:\test.txt", true, Encoding.UTF8);
             List<string> list = new List<string>();
             while ( == )
             {
                 string str = "CCKD";
                 str += GetRandomizer(, true, false, false, true);
                 if (!list.Contains(str))
                 {
                     list.Add(str);
                     sw.WriteLine(str);
                     sw.Flush();
                 }
                 if (list.Count== )
                     break;
             }
             sw.Close();
         }