Whats the difference between these two comparison statements?

Question

Whats the difference between these two comparison statments?

var result = EqualityComparer<T>.Default.Equals(@this, null);
var result = @this == null;

Obviously the aim is to test whether the object '@this' isnull.

Answer 1

Well it depends on the type of @this. If it doesn't have an overload of ==, the second line will just perform a direct reference comparison, whereas the first line will call an overridden Equals method or an implementation of IEquatable.Equals.

Any sensible implementation will give the same result for both comparisons.