if (<object> == )

Question

I can\'t understand, why the if statement in the picture below returns false. I hope you can explain it to me.

You can see, that the values and the typs

Answer 1

The == operator you are calling is the overload that takes two object parameters. This uses reference equality - the value isn't important, it has to be the same object.

As you can read in the documentation:

For reference types other than string, == returns true if its two operands refer to the same object. For the string type, == compares the values of the strings.

While int is a value type, it has been 'boxed' (wrapped in an object). You are comparing the two different reference types that wrap your integers.

To fix this, you can use object.Equals instead - this will compare the two integers.

item.Equals(value);

Or the static method (which would handle the case where item == null):

object.Equals(item, value);

If you unbox to int then you can use the int overload of == as you expect:

(int)item == (int)value;

Again, per the docs:

For predefined value types, the equality operator (==) returns true if the values of its operands are equal.