Hiding rather than closing a System.Windows.Window - problem

Question

Hi all I want to hide a System.Windows.Window when it is closed (via the [X] control or Alt-F4). I've seen a few different places say that the solution is to handle the Closing event with a CancelEventHandler as such: private void MyWindowClosing(object sender CancelEventArgs e) { e.Cancel = true; this.Hide(); } However when I do this I get the error: Cannot set visibility or call Show ShowDialog Close or Hide while window is closing. I am using .NET 3.0 and WPF. Am I doing something wrong or is there now a different way to achieve this? Thanks very much Keiron

Alan · Answer

I've done very little so far with WPF but it does say in the documentation that (unlike Windows Forms) you can't hide a window when it's closing: http://msdn2.microsoft.com/en-us/library/system.windows.window.closing.aspx All I can think of is to try adding a second handler to the Closing event which hides the form. By then the Closing event will have been cancelled by the first handler and the new state of the Cancel property should be persisted within the CancelEventArgs object passed to the second handler. However I'm not at all sure that this will work as the window might still be regarded as 'closing' because that's the event that has invoked both handlers.

Jan Montano · Answer

Hi Keiron For .net 2.0 I used this: private void Form1_Load(object sender EventArgs e) { this.FormClosing += new FormClosingEventHandler(form1_FormClosing); } void form1_FormClosing(object sender FormClosingEventArgs e) { e.Cancel = true; this.Hide(); } And it works fine.