expose and raise event of a child control in a usercontrol in c#

问题

Hi. I have a UserControl which contains a textbox. I wanted to access the textchanged event of the textbox but in the event properties of the usercontrol I don\'t see the events for the textbox. How can I expose and handle particular events of the child controls from the publicly exposed UserControl in Winforms with C#.

回答1:

You can surface a new event and pass any subscriptions straight through to the control, if you like:

public class UserControl1 : UserControl 
{
    // private Button saveButton;

    public event EventHandler SaveButtonClick
    {
        add { saveButton.Click += value; }
        remove { saveButton.Click -= value; }
    }
}

回答2:

Expose the entire TextBox as a public property in user control and subscribe to it's events the way you desire.
Example:

class myUserControl: UserControl { 
private TextBox _myText;
public TextBox MyText { get {return _myText; } }

}

After doing this you can subscribe on any of its events like so:

theUserControl.MyText.WhatEverEvent += ... 

Hope this helps!

来源：https://stackoverflow.com/questions/943171/expose-and-raise-event-of-a-child-control-in-a-usercontrol-in-c-sharp