Why we use “this” in Extension Methods?

Question

I want to ask why we use \"this\" keyword before the parameter in an extension method (C# Language)........... like this function :

    public static int ToI         


        

Answer 1

It's just the syntax that was chosen to indicate an extension method. Here's an interesting view point on the extension method syntax differences between C# and vb.net: Extension Method Implementation differences between C# and VB.NET