在接受的答案中添加了一些补充代码。它改进了仅使用随机的答案，并允许一些密码选项。我也喜欢KeePass回答中的一些选项，但不想在我的解决方案中包含可执行文件。

private string RandomPassword(int length, bool includeCharacters, bool includeNumbers, bool includeUppercase, bool includeNonAlphaNumericCharacters, bool includeLookAlikes)
{
    if (length < 8 || length > 128) throw new ArgumentOutOfRangeException("length");
    if (!includeCharacters && !includeNumbers && !includeNonAlphaNumericCharacters) throw new ArgumentException("RandomPassword-Key arguments all false, no values would be returned");

    string pw = "";
    do
    {
        pw += System.Web.Security.Membership.GeneratePassword(128, 25);
        pw = RemoveCharacters(pw, includeCharacters, includeNumbers, includeUppercase, includeNonAlphaNumericCharacters, includeLookAlikes);
    } while (pw.Length < length);

    return pw.Substring(0, length);
}

private string RemoveCharacters(string passwordString, bool includeCharacters, bool includeNumbers, bool includeUppercase, bool includeNonAlphaNumericCharacters, bool includeLookAlikes)
{
    if (!includeCharacters)
    {
        var remove = new string[] { "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" };
        foreach (string r in remove)
        {
            passwordString = passwordString.Replace(r, string.Empty);
            passwordString = passwordString.Replace(r.ToUpper(), string.Empty);
        }
    }

    if (!includeNumbers)
    {
        var remove = new string[] { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9" };
        foreach (string r in remove)
            passwordString = passwordString.Replace(r, string.Empty);
    }

    if (!includeUppercase)
        passwordString = passwordString.ToLower();

    if (!includeNonAlphaNumericCharacters)
    {
        var remove = new string[] { "!", "@", "#", "$", "%", "^", "&", "*", "(", ")", "-", "_", "+", "=", "{", "}", "[", "]", "|", "\\", ":", ";", "<", ">", "/", "?", "." };
        foreach (string r in remove)
            passwordString = passwordString.Replace(r, string.Empty);
    }

    if (!includeLookAlikes)
    {
        var remove = new string[] { "(", ")", "0", "O", "o", "1", "i", "I", "l", "|", "!", ":", ";" };
        foreach (string r in remove)
            passwordString = passwordString.Replace(r, string.Empty);
    }

    return passwordString;
}

这是我搜索生成随机密码时的第一个链接，以下内容超出了当前问题的范围，但可能很重要，需要考虑。

假设System.Web.Security.Membership.GeneratePassword是加密安全的，至少有20%的字符是非字母数字。 不确定在这种情况下删除字符和追加字符串是否被认为是良好的实践，并提供足够的熵。 可能需要考虑以某种方式使用SecureString实现内存中的安全密码存储。

public string Sifre_Uret(int boy, int noalfa)
{

    //  01.03.2016   
    // Genel amaçlı şifre üretme fonksiyonu


    //Fonskiyon 128 den büyük olmasına izin vermiyor.
    if (boy > 128 ) { boy = 128; }
    if (noalfa > 128) { noalfa = 128; }
    if (noalfa > boy) { noalfa = boy; }


    string passch = System.Web.Security.Membership.GeneratePassword(boy, noalfa);

    //URL encoding ve Url Pass + json sorunu yaratabilecekler pass ediliyor.
    //Microsoft Garanti etmiyor. Alfa Sayısallar Olabiliyorimiş . !@#$%^&*()_-+=[{]};:<>|./?.
    //https://msdn.microsoft.com/tr-tr/library/system.web.security.membership.generatepassword(v=vs.110).aspx


    //URL ve Json ajax lar için filtreleme
    passch = passch.Replace(":", "z");
    passch = passch.Replace(";", "W");
    passch = passch.Replace("'", "t");
    passch = passch.Replace("\"", "r");
    passch = passch.Replace("/", "+");
    passch = passch.Replace("\\", "e");

    passch = passch.Replace("?", "9");
    passch = passch.Replace("&", "8");
    passch = passch.Replace("#", "D");
    passch = passch.Replace("%", "u");
    passch = passch.Replace("=", "4");
    passch = passch.Replace("~", "1");

    passch = passch.Replace("[", "2");
    passch = passch.Replace("]", "3");
    passch = passch.Replace("{", "g");
    passch = passch.Replace("}", "J");


    //passch = passch.Replace("(", "6");
    //passch = passch.Replace(")", "0");
    //passch = passch.Replace("|", "p");
    //passch = passch.Replace("@", "4");
    //passch = passch.Replace("!", "u");
    //passch = passch.Replace("$", "Z");
    //passch = passch.Replace("*", "5");
    //passch = passch.Replace("_", "a");

    passch = passch.Replace(",", "V");
    passch = passch.Replace(".", "N");
    passch = passch.Replace("+", "w");
    passch = passch.Replace("-", "7");





    return passch;



}

我知道这是一个旧线程，但我有什么可能是一个相当简单的解决方案供某人使用。易于实现、易于理解、易于验证。

考虑以下要求:

我需要一个随机密码生成，其中至少有2个小写字母，2个大写字母和2个数字。密码长度至少为8个字符。

下面的正则表达式可以验证这种情况:

^(?=\b\w*[a-z].*[a-z]\w*\b)(?=\b\w*[A-Z].*[A-Z]\w*\b)(?=\b\w*[0-9].*[0-9]\w*\b)[a-zA-Z0-9]{8,}$

这超出了这个问题的范围——但是正则表达式是基于前向/后向和前后向的。

下面的代码将创建一个匹配这个要求的随机字符集:

public static string GeneratePassword(int lowercase, int uppercase, int numerics) {
    string lowers = "abcdefghijklmnopqrstuvwxyz";
    string uppers = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";
    string number = "0123456789";

    Random random = new Random();

    string generated = "!";
    for (int i = 1; i <= lowercase; i++)
        generated = generated.Insert(
            random.Next(generated.Length), 
            lowers[random.Next(lowers.Length - 1)].ToString()
        );

    for (int i = 1; i <= uppercase; i++)
        generated = generated.Insert(
            random.Next(generated.Length), 
            uppers[random.Next(uppers.Length - 1)].ToString()
        );

    for (int i = 1; i <= numerics; i++)
        generated = generated.Insert(
            random.Next(generated.Length), 
            number[random.Next(number.Length - 1)].ToString()
        );

    return generated.Replace("!", string.Empty);

}

要满足上述要求，只需调用以下命令:

String randomPassword = GeneratePassword(3, 3, 3);

代码以一个无效字符(“!”)开始——这样字符串就有一个长度，可以向其中注入新字符。

然后，它从1循环到所需的小写字符#，在每次迭代中，从小写列表中抓取一个随机项，并将其注入字符串中的随机位置。

然后对大写字母和数字重复循环。

这将返回长度=小写字母+大写字母+数字的字符串，其中您想要的计数的小写字母、大写字母和数字字符已按随机顺序放置。

我创建的这个方法类似于会员资格提供程序中可用的方法。如果你不想在某些应用程序中添加web引用，这是很有用的。

效果很好。

public static string GeneratePassword(int Length, int NonAlphaNumericChars)
    {
        string allowedChars = "abcdefghijkmnopqrstuvwxyzABCDEFGHJKLMNOPQRSTUVWXYZ0123456789";
        string allowedNonAlphaNum = "!@#$%^&*()_-+=[{]};:<>|./?";
        Random rd = new Random();

        if (NonAlphaNumericChars > Length || Length <= 0 || NonAlphaNumericChars < 0)
            throw new ArgumentOutOfRangeException();

            char[] pass = new char[Length];
            int[] pos = new int[Length];
            int i = 0, j = 0, temp = 0;
            bool flag = false;

            //Random the position values of the pos array for the string Pass
            while (i < Length - 1)
            {
                j = 0;
                flag = false;
                temp = rd.Next(0, Length);
                for (j = 0; j < Length; j++)
                    if (temp == pos[j])
                    {
                        flag = true;
                        j = Length;
                    }

                if (!flag)
                {
                    pos[i] = temp;
                    i++;
                }
            }

            //Random the AlphaNumericChars
            for (i = 0; i < Length - NonAlphaNumericChars; i++)
                pass[i] = allowedChars[rd.Next(0, allowedChars.Length)];

            //Random the NonAlphaNumericChars
            for (i = Length - NonAlphaNumericChars; i < Length; i++)
                pass[i] = allowedNonAlphaNum[rd.Next(0, allowedNonAlphaNum.Length)];

            //Set the sorted array values by the pos array for the rigth posistion
            char[] sorted = new char[Length];
            for (i = 0; i < Length; i++)
                sorted[i] = pass[pos[i]];

            string Pass = new String(sorted);

            return Pass;
    }

这是我快速拼凑的东西。

    public string GeneratePassword(int len)
    {
        string res = "";
        Random rnd = new Random();
        while (res.Length < len) res += (new Func<Random, string>((r) => {
            char c = (char)((r.Next(123) * DateTime.Now.Millisecond % 123)); 
            return (Char.IsLetterOrDigit(c)) ? c.ToString() : ""; 
        }))(rnd);
        return res;
    }

这个包允许你生成一个随机密码，同时流利地指出它应该包含哪些字符(如果需要):

https://github.com/prjseal/PasswordGenerator/

例子:

var pwd = new Password().IncludeLowercase().IncludeUppercase().IncludeSpecial();
var password = pwd.Next();