Checking an objects type or implemented interfaces

A common thing people might want to do is check if a object is a certain type, or inherits a type, or implements a type.

This can be done in VB.Net with the following code:

TypeOf someObject Is ClassName

This works for inheritance heirarchy as well as checking for interface implementation.

Here is a sample app showing it in practice.

imports Microsoft.VisualBasic
imports System
Imports System.Collections.Generic

public module MyModule
    sub Main
dim o as new subclass
        WL(typeof o is subclass)
        WL(typeof o is baseclass)
        WL(typeof o is IWhatever)
        RL()
    end sub

    #region "Helper methods"

    sub WL(text as object)
        Console.WriteLine(text)
    end sub

    sub WL(text as object, paramarray args as object())
        Console.WriteLine(text.ToString(), args)
    end sub
        
    sub RL()
        Console.ReadLine()
    end sub
    
    sub Break()
        System.Diagnostics.Debugger.Break()
    end sub

#end region

end module


public interface IWhatever
end interface
public class BaseClass

end class

public class SubClass
inherits BaseClass
implements IWhatever

end class
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