Question

We use controls all the time for example a button and sometimes we may want to add some custom properties to that button. For example numberOfTimesClicked etc. I am currently working with GridViewColumnHeader and I would like to add the property columnIndex to that class. I know I can keep track of the columns with other methods but I am just curios to know if we can add extra properties to classes. For example I was thinking about inheritance. If I create a new class and inherit from the class that I want to add new properties (in my case GridViewColumnHeader) then I think that should work but for some reason I get errors in my code whenever I do something like:

private class MyGridViewColumnHeader : GridViewColumnHeader
{
    public int propertyThatIWantToAdd { get; set; }
}

from now on if I instantiate objects from MyGridViewColumnHeader class instead of GridViewColumnHeader class I get errors. What is wrong with using inheritance to achieve this?

Answer 1

Instead of casting the sender object use

e.OriginalSource as MyGridViewColumnHeader

And do your work on that object. If you need to know what is inside the RoutedEventArgs have a look on MSDN