C#中的==和Equals()

class Program
     {
        public static bool EqualityTest1( object o1, object o2)
        {
            return o1.Equals(o2);
        }

        public static bool EqualityTest2(object o1 , object o2)
        {
            return o1 == o2;
        }
        static void Main(string[] args)
        {
             int i1 = 4;
             int i2 = 4;
            string s1 = "Hello!" ;
            string s2 = "Hello!";
            string s3 = new string (new char[] { 'H', 'e', 'l' , 'l', 'o', '!' });
            //Now let's look at some simple methods to compare equality.


            Console.WriteLine(EqualityTest1 (i1, i1));
            Console. WriteLine(EqualityTest2(i1, i1));

            // Compare i1 to i2
             Console.WriteLine(EqualityTest1(i1, i2 ));
            Console.WriteLine(EqualityTest2(i1, i2));

            // Compare s1 to s2
            Console.WriteLine(EqualityTest1 (s1, s2));
            Console. WriteLine(EqualityTest2(s1, s2));

            // Compare s2 to s3
             Console.WriteLine(EqualityTest1(s2, s3 ));
            Console.WriteLine(EqualityTest2(s2, s3));
        }
     }

运行结果有点出人意料，但是还是解释的通的。