Stack Overflow in random number generator

Question

For some reason, this code works fine when I don't use a seed in the Random class, but if I try to use DateTime.Now to get a more random number, I get a StackOverflowException! My class is really simple. Could someone tell me what I'm doing wrong here? See MakeUniqueFileName.

public class TempUtil
{
    private int strcmp(string s1, string s2)
    {
        try
        {
            for (int i = 0; i < s1.Length; i++)
                if (s1[i] != s2[i]) return 0;
            return 1;
        }
        catch (IndexOutOfRangeException)
        {
            return 0;
        }
    }
    private int Uniqueness(object randomObj)
    {
        switch (randomObj.ToString())
        {
            case "System.Object":
            case "System.String":
                return randomObj.ToString()[0];
            case "System.Int32":
                return int.Parse(randomObj.ToString());
            case "System.Boolean":
                return strcmp(randomObj.ToString(), "True");
            default:
                return Uniqueness(randomObj.ToString());
        }
    }
    public string MakeUniqueFileName()
    {
        return "C:\\windows\\temp\\" + new Random(Uniqueness(DateTime.Now)).NextDouble() + ".tmp";
    }
}

Answer 1

In short:

It should say

    switch (randomObj.GetType().ToString())

instead of

    switch (randomObj.ToString())

But even then this isn't very clever.