.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：
1 #region 生成指定长度的随机字符串 2 /// <summary> 3 /// 生成指定长度的随机字符串 4 /// </summary> 5 /// <param name="intLength">随机字符串长度</param> 6 /// <param name="booNumber">生成的字符串中是否包含数字</param> 7 /// <param name="booSign">生成的字符串中是否包含符号</param> 8 /// <param name="booSmallword">生成的字符串中是否包含小写字母</param> 9 /// <param name="booBigword">生成的字符串中是否包含大写字母</param> 10 /// <returns></returns> 11 public string GetRandomizer(int intLength, bool booNumber, bool booSign, bool booSmallword, bool booBigword) 12 { 13 //定义 14 Random ranA = new Random(); 15 int intResultRound = 0; 16 int intA = 0; 17 string strB = ""; 18 19 while (intResultRound < intLength) 20 { 21 //生成随机数A，表示生成类型 22 //1=数字，2=符号，3=小写字母，4=大写字母 23 24 intA = ranA.Next(1, 5); 25 26 //如果随机数A=1，则运行生成数字 27 //生成随机数A，范围在0-10 28 //把随机数A，转成字符 29 //生成完，位数+1，字符串累加，结束本次循环 30 31 if (intA == 1 && booNumber) 32 { 33 intA = ranA.Next(0, 10); 34 strB = intA.ToString() + strB; 35 intResultRound = intResultRound + 1; 36 continue; 37 } 38 39 //如果随机数A=2，则运行生成符号 40 //生成随机数A，表示生成值域 41 //1：33-47值域，2：58-64值域，3：91-96值域，4：123-126值域 42 43 if (intA == 2 && booSign == true) 44 { 45 intA = ranA.Next(1, 5); 46 47 //如果A=1 48 //生成随机数A，33-47的Ascii码 49 //把随机数A，转成字符 50 //生成完，位数+1，字符串累加，结束本次循环 51 52 if (intA == 1) 53 { 54 intA = ranA.Next(33, 48); 55 strB = ((char)intA).ToString() + strB; 56 intResultRound = intResultRound + 1; 57 continue; 58 } 59 60 //如果A=2 61 //生成随机数A，58-64的Ascii码 62 //把随机数A，转成字符 63 //生成完，位数+1，字符串累加，结束本次循环 64 65 if (intA == 2) 66 { 67 intA = ranA.Next(58, 65); 68 strB = ((char)intA).ToString() + strB; 69 intResultRound = intResultRound + 1; 70 continue; 71 } 72 73 //如果A=3 74 //生成随机数A，91-96的Ascii码 75 //把随机数A，转成字符 76 //生成完，位数+1，字符串累加，结束本次循环 77 78 if (intA == 3) 79 { 80 intA = ranA.Next(91, 97); 81 strB = ((char)intA).ToString() + strB; 82 intResultRound = intResultRound + 1; 83 continue; 84 } 85 86 //如果A=4 87 //生成随机数A，123-126的Ascii码 88 //把随机数A，转成字符 89 //生成完，位数+1，字符串累加，结束本次循环 90 91 if (intA == 4) 92 { 93 intA = ranA.Next(123, 127); 94 strB = ((char)intA).ToString() + strB; 95 intResultRound = intResultRound + 1; 96 continue; 97 } 98 99 } 100 101 //如果随机数A=3，则运行生成小写字母 102 //生成随机数A，范围在97-122 103 //把随机数A，转成字符 104 //生成完，位数+1，字符串累加，结束本次循环 105 106 if (intA == 3 && booSmallword == true) 107 { 108 intA = ranA.Next(97, 123); 109 strB = ((char)intA).ToString() + strB; 110 intResultRound = intResultRound + 1; 111 continue; 112 } 113 114 //如果随机数A=4，则运行生成大写字母 115 //生成随机数A，范围在65-90 116 //把随机数A，转成字符 117 //生成完，位数+1，字符串累加，结束本次循环 118 119 if (intA == 4 && booBigword == true) 120 { 121 intA = ranA.Next(65, 89); 122 strB = ((char)intA).ToString() + strB; 123 intResultRound = intResultRound + 1; 124 continue; 125 } 126 } 127 return strB; 128 129 } 130 #endregion
读取数据：
1 private void button1_Click(object sender, EventArgs e) 2 { 3 foreach (var file in Directory.GetFiles("E:\renew", "*.txt").Where(t => t.ToLower().EndsWith(".txt")).ToList()) 4 { 5 using (StreamReader reader = new StreamReader(file, Encoding.UTF8)) 6 { 7 string strLine = string.Empty; 8 while ((strLine = reader.ReadLine()) != null) 9 { 10 renewModel.Content = strLine; 11 renewBLL.Add(renewModel); 12 } 13 } 14 } 15 }
写入数据：
1 private void button2_Click(object sender, EventArgs e) 2 { 3 StreamWriter sw = new StreamWriter(@"E: est.txt", true, Encoding.UTF8); 4 List<string> list = new List<string>(); 5 while (1 == 1) 6 { 7 string str = "CCKD"; 8 str += GetRandomizer(5, true, false, false, true); 9 if (!list.Contains(str)) 10 { 11 list.Add(str); 12 sw.WriteLine(str); 13 sw.Flush(); 14 } 15 if (list.Count== 100000) 16 break; 17 } 18 sw.Close(); 19 }