Difference between DeclaringType and ReflectedType

They’re not exactly the same.

• DeclaringType returns the type that declares the method.
• ReflectedType returns the Type object that was used to retrieve the method.

Here’s a demo:

MemberInfo m1 = typeof(Base).GetMethod("Method");
MemberInfo m2 = typeof(Derived).GetMethod("Method");

Console.WriteLine(m1.DeclaringType); //Base
Console.WriteLine(m1.ReflectedType); //Base

Console.WriteLine(m2.DeclaringType); //Base
Console.WriteLine(m2.ReflectedType); //Derived

public  class Base
{
    public void Method() {}
}

public class Derived : Base { }

Noticed how the last line printed Derived instead of Base. That’s because, even though Method is declared on Base, we used Derived to obtain the MemberInfo object.

Source: MSDN