字符串驻留池

class Program
{
    static void Main(string[] args)
    {
        internPool();
        Console.Read();
    }

    //http://www.cnblogs.com/instance/archive/2011/05/24/2056091.html
    static void internPool()//clr string 字符串驻留池机制，字面量字符串使用这个机制来节省内存
    {
        
        // clr初始化时会自动初始化 string.empty字符串，放到clr的字符串驻留池中
        Console.WriteLine(string.IsInterned(string.Empty) != null);
        Console.WriteLine(string.IsInterned("") != null);

        Console.WriteLine();

        var s1 = "hello";
        var s2 = "hello";

        Console.WriteLine(object.ReferenceEquals(s1,s2));//true

        var sb = new StringBuilder().Append("he").Append("llo");
        Console.WriteLine(object.ReferenceEquals(s1,sb.ToString()));//falae
        Console.WriteLine(object.ReferenceEquals(s1,string.Intern(sb.ToString())));//true

        var s3 = "";
        var s4 = string.Empty;
        Console.WriteLine(object.ReferenceEquals(s3,s4));//true
        
    }
}