Q:

How to inform parent control when UserControl perform method call?

I have MainForm on which i've loaded UserControl. This UserControl has few textboxes and save button. Once i click save, information from textboxes is saved to file. I want to inform MainForm that information is updated to it can reload.
How can i do that ?

A:

Use events.
Declare an event in your UserControl, for instance:
public event EventHandler SaveClicked;

then on save click, raise the event:
if (this.SaveClicked != null)
{
    this.SaveClicked(this, EventArgs.Empty);
}

and finally attach a handler in the main form to your event:
...
YourUserControl ctrl = new YourUserControl();
ctrl.SaveClicked += (sender, e) =>
{
    // Put logic of your main form here
};

