User Control Events

I have a user control with a button开发者_如何学JAVA named upload in it. The button click event looks like this:

 protected void btnUpload_Click(object sender, EventArgs e)
{
  // Upload the files to the server
}

On the page where the user control is present, after the user clicks on the upload button I want to perform some operation right after the button click event code is executed in the user control. How do I tap into the click event after it has completed its work?

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You have to create an event in your user control, something like:

public event EventHandler ButtonClicked;

and then in your method fire the event...

protected void btnUpload_Click(object sender, EventArgs e)
{
   // Upload the files to the server

   if(ButtonClicked!=null)
      ButtonClicked(this,e);
}

Then you will be able to attach to the ButtonClicked event of your user control.

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Create a Public Property in UserControl's CodeBehind:

    public Button btn
    {
        get { return this.Button1; }
    }

Then on page_Load you can use it like:

    WebUserControl11.btn.Click += (s, ea) => { Response.Write("Page Write"); };

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Instead of writing an event handler just to call another event, you can instead directly wire the events together by using an explicit event implementation:

public event EventHandler ButtonClicked
{
   add { btnUpload.Click += value; }
   remove { btnUpload.Click -= value; }
}

Now anyone who subscribes to your ButtonClicked event is actually directly subscribing to the Click event of the btnUpload control. I find this to be a much more succinct way to implement this.