Question

I have public object LastControl which will contain custom classes, some of which have Resize() method. I want to know how to find out if current value is of a class that has this method and in that case run it.

As of now, I get errors when trying to compile LastControl.Resize() because the type object itself doesn’t have that method. Casting as control class could be an easy solution, but there are multiple classes, so I don’t know what to do here. I figured I should start with using GetType in some way.

Answer 1

The reflection-based way, as you alluded to by GetType, uses the GetMethod method. You can use it to get a MethodInfo instance on which you can then call the Invoke method to execute the method.

A cleaner way, however, would be to declare an interface that provides a Resize() method:

public interface IResizeable
{
    void Resize();
}

In any custom class of yours that has a Resize() method, you could implement that interface. Then, for checking whether the current value of LastControl has a Resize() method, you try to cast the object by using as, and if the result is not null, you can safely call the Resize() method:

IResizeable resizeable = LastObject as IResizeable;
if (resizeable != null) {
    resizeable.Resize();
}