C# difference between == and Equals()

c# .net equals
Drahcir picture Drahcir · May 2, 2009 · Viewed 319.4k times · Source

I have a condition in a silverlight application that compares 2 strings, for some reason when I use == it returns false while .Equals() returns true.

Here is the code:

if (((ListBoxItem)lstBaseMenu.SelectedItem).Content.Equals("Energy Attack"))
{
    // Execute code
}

if (((ListBoxItem)lstBaseMenu.SelectedItem).Content == "Energy Attack")
{
    // Execute code
}

Any reason as to why this is happening?

Answer

Mehrdad Afshari picture Mehrdad Afshari · May 2, 2009

When == is used on an expression of type object, it'll resolve to System.Object.ReferenceEquals.

Equals is just a virtual method and behaves as such, so the overridden version will be used (which, for string type compares the contents).

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