C# -用于随机化四个字符串的大小写的函数总是以相同的大小写返回每个字符串

using System;

public class Program
{
    public static void Main()
    {
        string[] strings = { "string1", "string2", "string3", "string4" };

        foreach (string str in strings)
        {
            string randomizedString = RandomizeStringCase(str);
            Console.WriteLine(randomizedString);
        }
    }

    public static string RandomizeStringCase(string str)
    {
        Random random = new Random();
        string randomizedString = "";

        foreach (char c in str)
        {
            if (random.Next(2) == 0)
                randomizedString += Char.ToUpper(c);
            else
                randomizedString += Char.ToLower(c);
        }

        return randomizedString;
    }
}