c# - Object equality behaves different in .NET

Question

I have these statements and their' results are near them.

string a = "abc";
string b = "abc";

Console.Writeline(a == b); //true

object x = a;
object y = b;

Console.Writeline(x == y); // true

string c = new string(new char[] {'a','b','c'});
string d = new string(new char[] {'a','b','c'});

Console.Writeline(c == d); // true

object k = c;
object m = d;

Console.Writeline(k.Equals(m)) //true

Console.Writeline(k == m); // false

Why the last equality gives me false ?

The question is why ( x == y ) is true ( k == m ) is false

Answer 1

In the case of strings, the == operator is overloaded to test for value equality, when using object reference equality is used.

Since c and d are strings, when you use Equals in the k and m, the overloaded method is used.

And c == d is true for the reason state above - value equality is used on string types as the operator is overloaded.