KeyDown event throws an exception when MessageBox.Show(e.Key.ToString()) is called

06-06-2009 6:43 PM |

The TextBox's event:

private void TextBox_KeyDown(object sender, KeyEventArgs e)
{
    MessageBox.Show(e.Key.ToString());
}

throws an exception on any key pressed just except the first one. 

It doesn't happen at all on the KeyUp event with the same code within.

What does it mean? 

Re: KeyDown event throws an exception when MessageBox.Show(e.Key.ToString()) is called

06-07-2009 8:30 AM |

Check this link:

http://blogs.vertigo.com/personal/keithc/Blog/archive/2008/12/02/keydown-and-messagebox-dont-mix-well-in-silverlight.aspx

Its will answer your post. Hope it helps you

Re: KeyDown event throws an exception when MessageBox.Show(e.Key.ToString()) is called

06-07-2009 7:31 PM |

 Thank for your explanation, but I still have some doubts:

If any other thread (event) tries to display MessageBox at the same time why can't I catch it at my breakpoint?

It's caught only once and sometimes drops on it. By the way, my Firefox drops too.

Then I added a TextBlock to check a chance of multiple KeyDown events and was putting every got key to the TextBlock's content.

But no multiple events occurred.