Compare String and Object in C#

Question

See this code:

object x = \"mehdi emrani\";
string y = \"mehdi emrani\";
Console.WriteLine(y == x);

that returns true.

Answer 1

In the first case, .NET performs string constant optimization and allocates only one String instance. Both x and y points to same object (both the references are equal).

But in the second case x and y are pointing to different String instances. Adding "ermani" to y creates a third string object.

"==" operator basically returns true if operands on both sides refer to same object. In the first case x and y refer to same object and in the seconds case x & y refer different objects.