如何制作长度为5的随机数字和字母字符串？ [复制]

可能的重复：
这是生成随机字符字符串的好方法吗？ https://stackoverflow.com/questions/976646/is-this-a-good-way-to-generate-a-string-of-random-characters
如何在 C# 中生成随机 8 个字符的字母数字字符串？ https://stackoverflow.com/questions/1344221/how-can-i-generate-random-8-character-alphanumeric-strings-in-c

这是我到目前为止所拥有的代码。

    private void button1_Click(object sender, EventArgs e)
    {
        string rand1 = RandomString(5);
        string rand2 = RandomString(5);
        string rand3 = RandomString(5);
        string rand4 = RandomString(5);
        string rand5 = RandomString(5);
        textBox1.Text = rand1 + "-" + rand2 + "-" + rand3 + "-" + rand4 + "-" + rand5;

    }
    private static Random random = new Random((int)DateTime.Now.Ticks);
    private string RandomString(int Size)
    {
        StringBuilder builder = new StringBuilder();
        char ch;
        for (int i = 0; i < Size; i++)
        {
            ch = Convert.ToChar(Convert.ToInt32(Math.Floor(26 * random.NextDouble() + 65)));
            builder.Append(ch);
        }
        return builder.ToString();
    }

但它只是创建一个 5 个字符的随机字符串。 我希望它创建一个由 5 个字符和整数组成的字符串。 我该怎么做？提前致谢！

使用输入数组从中提取值：

private static string RandomString(int length)
{
    const string pool = "abcdefghijklmnopqrstuvwxyz0123456789";
    var builder = new StringBuilder();

    for (var i = 0; i < length; i++)
    {
        var c = pool[random.Next(0, pool.Length)];
        builder.Append(c);
    }

    return builder.ToString();
}

或者（不可避免的）Linq 解决方案：

private static string RandomString(int length)
{
    const string pool = "abcdefghijklmnopqrstuvwxyz0123456789";
    var chars = Enumerable.Range(0, length)
        .Select(x => pool[random.Next(0, pool.Length)]);
    return new string(chars.ToArray());
}