C# 随机数问题 分数不是问题

Question

1、如何随机生成N个随机字母的组合：如N=3， abc、asd、aas、ccs等等
2、如何随机生成M个随机数字的组合：如N=5，12342、21354、21456
分数不是问题。

Answer 1

笨方法   
Random ra =new Random();
            string pt="";
            int res=0;
            switch (pt)
            {
                case "3":
                   res= ra.Next(100, 999);
                    break;
                 case "5":
                    res=  ra.Next(10000, 99999);
                    break;
                    .....
            }

Answer 2

        // 生成随机数字
        // <param name="length">生成长度</param>
        public static string Number(int Length)
        {
            return Number(Length, false);
        }        /// 生成随机数字
        /// <param name="Length">生成长度</param>
        /// <param name="Sleep">是否要在生成前将当前线程阻止以避免重复</param>
        public static string Number(int Length,bool Sleep)
        {
            if(Sleep)
                System.Threading.Thread.Sleep(3);
            string result = "";
            System.Random random = new Random();
            for (int i = 0; i < Length; i++)
            {
                result += random.Next(10).ToString();
            }
            return result;
        }
/// <summary>
        /// 生成随机纯字母随机数
        /// </summary>
        /// <param name="IntStr">生成长度</param>
        /// <returns></returns>
        public static string Str_char(int Length)
        {
            return Str_char(Length, false);
        }        /// <summary>
        /// 生成随机纯字母随机数
        /// </summary>
        /// <param name="Length">生成长度</param>
        /// <param name="Sleep">是否要在生成前将当前线程阻止以避免重复</param>
        /// <returns></returns>
        public static string Str_char(int Length, bool Sleep)
        {
            if (Sleep) System.Threading.Thread.Sleep(3);
            char[] Pattern = new char[] { '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' };
            string result = "";
            int n = Pattern.Length;
            System.Random random = new Random(~unchecked((int)DateTime.Now.Ticks));
            for (int i = 0; i < Length; i++)
            {
                int rnd = random.Next(0, n);
                result += Pattern[rnd];
            }
            return result;
        }
    } 

Answer 3

字母随机或者：/// <summary> 
/// 字母随机数 
/// </summary> 
/// <param name="n">生成长度</param> 
/// <returns></returns> 
public static string RandLetter(int n) 
{ 
char[] arrChar = new char[]{ 
'a','b','d','c','e','f','g','h','i','j','k','l','m','n','p','r','q','s','t','u','v','w','z','y','x', 
'_', 
'A','B','C','D','E','F','G','H','I','J','K','L','M','N','Q','P','R','T','S','V','U','W','X','Y','Z' 
}; 
StringBuilder num = new StringBuilder(); 
Random rnd = new Random(DateTime.Now.Millisecond); 
for (int i = 0; i < n; i++) 
{ 
num.Append(arrChar[rnd.Next(0, arrChar.Length)].ToString()); 
} 
return num.ToString(); 
} 

Answer 4

字母随机或者：/// <summary> 
/// 字母随机数 
/// </summary> 
/// <param name="n">生成长度</param> 
/// <returns></returns> 
public static string RandLetter(int n) 
{ 
char[] arrChar = new char[]{ 
'a','b','d','c','e','f','g','h','i','j','k','l','m','n','p','r','q','s','t','u','v','w','z','y','x', 
'_', 
'A','B','C','D','E','F','G','H','I','J','K','L','M','N','Q','P','R','T','S','V','U','W','X','Y','Z' 
}; 
StringBuilder num = new StringBuilder(); 
Random rnd = new Random(DateTime.Now.Millisecond); 
for (int i = 0; i < n; i++) 
{ 
num.Append(arrChar[rnd.Next(0, arrChar.Length)].ToString()); 
} 
return num.ToString(); 
} 

Answer 5

           string[] s = new string[26]{"a","b","c","d","e","f","g",...};            Random ran = new Random();
            int n = 0;
            int m=0;            string nValue = "";
            string mValue = "";
            int index = 0;
            for(int i = 0;i<n;i++)
            {
                 index = ran.Next(0,25);                 nValue += s[index];
            }            for(int i=0;i<m;i++)
            {
                index = ran.Next(0,9);
                mValue += index.ToString();
            }

Answer 6

 StringBuilder sb = new StringBuilder();
        string Table = "abcdefghijklmnopqrstuvwxyz";        int[] p = new int[26];//字符索引
        int Length = 3 - 1;//字符串的长度
        int i = Length;
        p[i] = -1;
        int a = 0;
        while (a++ <= Length) sb.Append("a");
        while (i > -1)
        {
            if (p[i] == 25)
            {
                sb.Remove(i, 1);
                i--;
                continue;
            }
            else
            {
                p[i] = p[i] + 1;
                sb[i] = Table[p[i]];
                if (i < Length)
                {
                    i++;
                    p[i] = -1;
                    sb.Append(" ");
                    continue;
                }
            }
            Response.Write(sb.ToString() + "<br/>");
        }
或者把值存入ISET里来查

Answer 7

/// <summary>
/// 生成随机数
/// </summary>
/// <param name="pwdLength">参数值</param>
/// <returns></returns>
public static string MakePassword(int PwdLength)
{
string Tmp = "";
string pwd ="abcdefghkmnpqrstuvwxyz23456789ABCDEFGHKMNPQRSTUVWXYZ";
int MakeRandNum;
Random rnd = new Random();
for(int i=0;i<PwdLength;i++)
{
MakeRandNum = rnd.Next(pwd.Length);
Tmp += pwd[MakeRandNum];
}
return Tmp;
}

Answer 8

/// <summary>
        /// 生成随机字符串
        /// </summary>
        /// <param name="length">目标字符串的长度</param>
        /// <param name="useNum">是否包含数字，1=包含，默认为包含</param>
        /// <param name="useLow">是否包含小写字母，1=包含，默认为包含</param>
        /// <param name="useUpp">是否包含大写字母，1=包含，默认为包含</param>
        /// <param name="useSpe">是否包含特殊字符，1=包含，默认为不包含</param>
        /// <param name="custom">要包含的自定义字符，直接输入要包含的字符列表</param>
        /// <returns>指定长度的随机字符串</returns>
        public string GetRnd(int length, bool useNum, bool useLow, bool useUpp, bool useSpe, string custom)
        {
            byte[] b = new byte[4];
            new System.Security.Cryptography.RNGCryptoServiceProvider().GetBytes(b);
            Random r = new Random(BitConverter.ToInt32(b, 0));
            string s = null, str = custom;            if (useNum == true) { str += "0123456789"; }
            if (useLow == true) { str += "abcdefghijklmnopqrstuvwxyz"; }
            if (useUpp == true) { str += "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; }
            if (useSpe == true) { str += "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~"; }            for (int i = 0; i < length; i++)
            {
                s += str.Substring(r.Next(0, str.Length - 1), 1);
            }            return s;
        }

Answer 9

<script type="text/javascript" language="javascript">function CreateStr()
{
 var j=document.getElementById("input2").value;
 if(isNaN(j))
 {
 alert("请输入整数");
 }
 var tmpCh = "";
 var i=1;
 for(i=1;i<=j;i++)
 {
 tmpCh += String.fromCharCode(Math.floor( Math.random() * 26) + "a".charCodeAt(0));
 }
 alert(tmpCh);
}
function CreateNo()
{ var j=document.getElementById("input3").value; if(isNaN(j))
 {
 alert("请输入整数");
 }var s = (Math.floor(Math.random()*10000) % j+1).toString();
for(var i=1;i<j; i++)
{
    s = s + (Math.floor(Math.random()*10000) % 10).toString();
}
alert(s);
}
</script>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
<HEAD>
<TITLE> New Document </TITLE></HEAD><BODY>
<input type="input" id="input2" />
<input type="button"  onclick="CreateStr()" value="生成随机字母" width="120px" height="28px"/>
<input type="input" id="input3" />
<input type="button"  onclick="CreateNo()" value="生成随机数" width="120px" height="28px"/>
</BODY>
</HTML>

Answer 10

private static StringBuilder getRandom( bool isOverlap, int number, int min, int max)
        {
            var sb = new StringBuilder();
            Random rd = new Random(Environment.TickCount + DateTime.Now.Millisecond);
            if (isOverlap)
            {
                for (int i = 0; i < number; i++)
                {
                    sb.Append(Convert.ToChar(rd.Next(min, max)));
                }
            }
            else
            {
                var Temporary = new List<char>();
                for (int i = 0; i < number; i++)
                {
                    while (true)
                    {
                        var isindex = Convert.ToChar(rd.Next(min, max));
                        if (Temporary.Contains(isindex))
                        {
                            continue;
                        }
                        else
                        {
                            Temporary.Add(isindex);
                            sb.Append(isindex);
                            break;
                        }
                    }
                }
            }
            return sb;
        }
 
        例子
            getRandom（不重复true，3个，）
             max = 123; min = 65;字母
              max = 58; min = 48; 数字

Answer 11

来一段儿，这个网上一搜一大把的/// <summary>
        /// 返回大写字母加数字的随机编码
        /// </summary>
        /// <param name="CodeLength"></param>
        /// <returns></returns>
        public static string GetRndCode(int CodeLength)
        {
            string Vchar = "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";            string[] VcArray = Vchar.Split(',');
            string RndCode = string.Empty;
            int temp = -1;  //记录上次随机数值            //采用一个简单的算法以保证生成随机数的不同
            Random rand = new Random();
            for (int i = 0; i < CodeLength; i++)
            {
                if (temp != -1)
                {
                    rand = new Random(i * temp * unchecked((int)DateTime.Now.Ticks));
                }
                int t = rand.Next(35);
                //如果出现与上次一样的字符，则重新生成一个
                if (temp != -1 && temp == t)
                {
                    return GetRndCode(CodeLength);
                }
                temp = t;
                RndCode += VcArray[t];
            }
            return RndCode;
        }