Test if a method is an override?

Question

Possible Duplicate:
Detect if a method was overridden using Reflection (C#)

Is there a way to tell if a method is an override? For e.g.

public class Foo
{
    public virtual void DoSomething() {}
    public virtual int GimmeIntPleez() { return 0; }
}

public class BabyFoo: Foo
{
    public override int GimmeIntPleez() { return -1; }
}

Is it possible to reflect on BabyFoo and tell if GimmeIntPleez is an override?

Duplicate? - http://stackoverflow.com/questions/2932421/detect-if-a-method-was-overridden-using-reflection-c — Petar Minchev, Jun 16 '10 at 18:07
Excellent! Many thanks, Petar. How do you find such threads? — Water Cooler v2, Jun 16 '10 at 18:09
@Rowland: At execution (aka run-time) time. At compile time, I could use a regex on the source file, if that was what you were alluding to. — Water Cooler v2, Jun 16 '10 at 18:10
Using the search function on StackOverflow(upper-right corner) - "C# method override" is just enough to find the threads. Also you can use google:) — Petar Minchev, Jun 16 '10 at 18:13

score 14 · Answer 1 · answered Jun 16 '10 at 18:11

14

Test against MethodInfo.GetBaseDefinition(). If the function is an override, it will return a different method in a base class. If it's not, the same method object will be returned.

When overridden in a derived class, returns the MethodInfo object for the method on the direct or indirect base class in which the method represented by this instance was first declared.

answered Jun 16 '10 at 18:11

zildjohn01

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+1 because you are the first one mentioning the GetBaseDefinition method, which I think is the correct way to figure out whether a method is an override. – Ciprian Bortos May 08 '11 at 04:34

score 4 · Accepted Answer · answered Jun 16 '10 at 18:08

You can use MethodInfo.DeclaringType to determine if the method is an override (assuming that it's also IsVirtual = true).

From the documentation:

...note that when B overrides virtual method M from A, it essentially redefines (or redeclares) this method. Therefore, B.M's MethodInfo reports the declaring type as B rather than A, even though A is where this method was originally declared...

Here's an example:

var someType = typeof(BabyFoo);
var mi = someType.GetMethod("GimmeIntPleez");
// assuming we know GimmeIntPleez is in a base class, it must be overriden
if( mi.IsVirtual && mi.DeclaringType == typeof(BabyFoo) )
    { ... }

My comment comes a bit late, but here it is. I don't think this solution will do because the BabyFoo type may declare its own virtual method with the same name but different parameters. This solution will not detect that. — Ciprian Bortos, May 08 '11 at 04:32

Test if a method is an override?

2 Answers2