C# 字符串复制()

public static string Copy(String str)

using System;  
    public class StringExample  
    {  
        public static void Main(string[] args)  
        {  
             string s1 = "Hello ";  
             string s2 = string.Copy(s1);
             Console.WriteLine(s1);
             Console.WriteLine(s2);
        }  
    }  

Hello
Hello