Private void tbox_keypress (Object sender, keypresseventargs E)
{
If (E. keychar = 0x20) E. keychar = (char) 0; // disable the Space key
If (E. keychar = 0x2d) & (textbox) sender). Text. Length =
0) return; // process negative numbers
If (E. keychar> 0x20)
{
Try
{
Double. parse (textbox) sender). Text + E. keychar. tostring ());
}
Catch
{
E. keychar = (char) 0; // handle invalid characters
}
}
}
Private void textbox_keypress (Object sender,
Keypresseventargs E)
{
If (E. keychar! = 8 &&! Char. isdigit (E. keychar ))
{
E. Handled = true;
}
}
Or private void
Textbox_keypress (Object sender, keypresseventargs E)
{
If (E. keychar! = '/B '&&! Char. isdigit (E. keychar ))
{
E. Handled = true;
}
}
Private void
Textboxshortkeypress (Object sender, system. Windows. Forms. keypresseventargs
E)
{
If (E. keychar! = '/B') // This indicates that the backspace key is allowed.
{
If (E. keychar <'0') |
(E. keychar> '9') // This is a 0-9 number.
{
E. Handled = true;
}
}
}
Private void button#click (Object sender,
Eventargs E)
{
String text = This. textbox1.text;
If (text! =
Null)
MessageBox. Show (text );
}
Private void
Textbox1_validating (Object sender, canceleventargs E)
{
Const
String Pattern = @ "^/d + /.? /D + $ ";
String content =
(Textbox) sender). text;
If (! (RegEx. ismatch (content, pattern )))
{
Errorprovider1.seterror (Control) sender, "only numbers can be entered! ");
E. Cancel =
True;
}
Else
Errorprovider1.seterror (Control) sender,
Null );
}
Private void textbox1_keypress (Object
Sender, system. Windows. Forms. keypresseventargs E)
{
If (E. keychar = '.'
& This. textbox1.text. indexof (".")! =-1)
{
E. Handled = true;
}
If (! (E. keychar> = 48 & E. keychar <= 57) |
E. keychar = '.' | E. keychar = 8 ))
{
E. Handled = true;
}
}
Private void tbx_lsregcapital_keypress (Object sender,
Keypresseventargs E)
{
If
(! Char. isnumber (E. keychar )&&! Char. ispunctuation (E. keychar)
&&! Char. iscontrol (E. keychar ))
{
E. Handled = true; // remove unsuitable characters
}
Else if
(Char. ispunctuation (E. keychar ))
{
If
(E. keychar! = '.' | This. textbox1.text. Length = 0) // decimal point
{
E. Handled = true;
}
If (textbox1.text. lastindexof ('.')! =-1)
{
E. Handled = true;
}
}
}
ASCII code,
{
If (E. keychar <= 48 | E. keychar> = 57) & (E. keychar! =
8) & (E. keychar! = 46 ))
E. Handled = true;
=====================48
Represents 0, 57 represents 9, 8 represents space, 46 represents the decimal point
}