I tryed to create my own numeric textbox here is my code:
public class NumericTextBox : TextBox
{
public NumericTextBox()
: base()
{
this.Text = "0";
}
private void HandleKeyEvent(KeyEventArgs e)
{
e.Handled = true;
if ((Keyboard.Modifiers & ModifierKeys.Alt) != 0)
{
return;
}
if (e.Key == Key.Back || e.Key == Key.Delete || e.Key == Key.Left || e.Key == Key.Right ||
e.Key == Key.D0 || e.Key == Key.D1 || e.Key == Key.D2 || e.Key == Key.D3 || e.Key == Key.D4 || e.Key == Key.D5 || e.Key == Key.D6 ||
e.Key == Key.D7 || e.Key == Key.D8 || e.Key == Key.D9 ||
e.Key == Key.NumPad0 || e.Key == Key.NumPad1 || e.Key == Key.NumPad2 || e.Key == Key.NumPad3 || e.Key == Key.NumPad4 || e.Key == Key.NumPad5 || e.Key == Key.NumPad6 ||
e.Key == Key.NumPad7 || e.Key == Key.NumPad8 || e.Key == Key.NumPad9)
{
e.Handled = false;
}
else if ((e.Key == Key.Subtract || (e.Key == Key.Unknown && e.PlatformKeyCode == 189)) && base.SelectionStart == 0 && (base.Text.Length == 0 || base.Text[0] != '-'))
{
e.Handled = false;
}
}
protected override void OnKeyDown(KeyEventArgs e)
{
HandleKeyEvent(e);
base.OnKeyDown(e);
}
protected override void OnKeyUp(KeyEventArgs e)
{
HandleKeyEvent(e);
base.OnKeyUp(e);
}
}
everything works like supposed but if you press alt and some numbers it creates the ascii symbol corresponding to the number.. is there any way to block an "alt + number combination?
it seems that alt + key just gets entered without going threw OnKeyUp or OnKeyDown...
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