CSharp/C#, PictureBox_KeyDown or PictureBox_KeyPress not firing

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CSharp/C# >> PictureBox_KeyDown or PictureBox_KeyPress not firing

by Christian Blackburn » Mon, 08 Sep 2008 05:28:25 GMT

Hi Gang,

Man is C# a heck of a lot harder to write events for than Visual
Basic. In any event I can't get the following code to fire when I
press a key on a picture box:
// Handle the KeyDown event to determine the type of character
entered into the control.
private void picLogo_KeyDown(object sender,
System.Windows.Forms.KeyEventArgs e)
{


MessageBox.Show(this, "you pressed a key", "keyboard",
MessageBoxButtons.OK, MessageBoxIcon.Information);

}

private void InitializeComponent()
{
this.picLogo.KeyDown += new
System.Windows.Forms.KeyEventHandler(this.picLogo_KeyDown);

}

I don't get any errors, but it just never fires :(.

Thanks for any and all help,
Christian Blackburn
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CSharp/C# >> PictureBox_KeyDown or PictureBox_KeyPress not firing

by Peter Duniho » Mon, 08 Sep 2008 06:18:50 GMT


On Sun, 07 Sep 2008 14:28:25 -0700, Christian Blackburn



Do you have VB.NET code that does the same thing and which works?

Just off the top of my head: are you sure that the PictureBox control has
focus when you are pressing the keys? My recollection is that it's one of
the "non-focusable" controls. You may be able to change that by
sub-classing PictureBox and setting the Selectable control style in the
constructor. But you may find it simpler to handle the key-press in the
container class (e.g. your form).

Keep in mind that you still have some UI issues:

-- Even if you allow PictureBox to accept focus by sub-classing, it
doesn't show focus by default. So either you'd have to add that, or you'd
have lack of good user presentation.

-- Even worse is the prospect of having a control react to key input
without having focus. In some scenarios this might work okay, but any
time you head down that path you should really reconsider whether that's
the right control/UI paradigm for the job.

Pete
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CSharp/C# >> PictureBox_KeyDown or PictureBox_KeyPress not firing

by raylopez99 » Mon, 08 Sep 2008 06:32:30 GMT

On Sep 7, 2:28爌m, Christian Blackburn < XXXX@XXXXX.COM >


Besides the stuff Peter D mentioned, which is generally good, keep in
mind the following stuff about keydown events in C#, which took me
half a day to figure out the hard way:

this.KeyPreview = true; that must be set to 憈rue?from Wizard for key
press event KeyUp or KeyDown to work, (in InitializeComponent(); it抯:
this.KeyPreview = true;)


RL
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