Question

I have my app with my labels written to centralize when its text was modified.

To make that I invoke a method through an EventHandler. I want to use same method to each one of my labels, but I don´t know how to identify in the method which label invoke it.

If I have a code like this:

       lbl_TextChanged(object sender, EventArgs e)
        {
           ..code..
           label1.Location = new Point("label's location");
           ..more code..
        }

and I invoke again that method from another label, how could I modify that code in order to know which label invoke it?

SOLUTION Thanks for the help, This is the first time I tried to make something with the event handler and didn’t know that I need to cast the sender. That solves my problem.

Thanks for the help!

Answer 1

The sender object in the event handler signature is the control that raised the event.

Simply cast this object and you have access to all the control’s information.

Label label = sender as Label;

You do need to be a little bit careful with this, since you are assuming that only controls of type Label are raising events that have this handler method.