Question

I want to write a method named IsExtensionMethod that its signature is :

public bool IsExtensionMethod(object anObject, string method)
{
    // if method was an extension for anObject return true else false
}

How can i do it?

I tried for following code but in some cases it’s return value is incorrect:

public bool IsExtensionMethod(object anObject, string method)
{
    return anObject.GetType().GetMethods().Where(item => item.Name == method).Count() == 0;
}

Answer 1

The compiler adds a CompilerServices.ExtensionAttribute attribute to extension methods when it compiles them. Look for this attribute.

http://www.hanselman.com/blog/HowDoExtensionMethodsWorkAndWhyWasANewCLRNotRequired.aspx