C# App: Numeric and Mathimatical Operators only TextBox

[LoanB]

Hi

I'm looking to ensure that my textbox only accepts numbers .. AND ... mathematical operators + - . / *. an dmaybe a blank space

I can ensure that only number are included by using:

private void txtSurname_KeyPress(object sender, KeyPressEventArgs e)
{
     if (e.Handled = !(Char.IsDigit(e.KeyChar)))
     {
         e.Handled = true;
     }   
}

OR

private void txtTel_KeyPress(object sender, KeyPressEventArgs e)
{
      if (((e.KeyChar < '0') || (e.KeyChar > '9')) && (e.KeyChar != '\b'))    
     {
         e.Handled = true;
     }
}
 

My Questions then:

1. Which one of the above is better to use to ensure that only numbers are
used?

2. How can I change the better option above to also allow me to input the
specified operators.

Thanks in advance,

Lóan

[LoanB]

Ok I managed to get it working doing the following,

 private void txtTel_KeyPress(object sender, KeyPressEventArgs e)
{
     if ((e.Handled = !(Char.IsDigit(e.KeyChar))) && (e.Handled =   
     !(Char.IsWhiteSpace(e.KeyChar))) && (e.Handled = 
     !(Char.IsPunctuation(e.KeyChar))) && (e.Handled = 
     !(Char.IsSymbol(e.KeyChar))) && (e.Handled = !(Char.IsControl(e.KeyChar))))
     {
         e.Handled = true;
     }
}
 

this works perfectly, but does anyone know how to do th eabove in a shorter version.

Cheers,

[Frinavale]

Ok I managed to get it working doing the following,

 private void txtTel_KeyPress(object sender, KeyPressEventArgs e)
{
     if ((e.Handled = !(Char.IsDigit(e.KeyChar))) && (e.Handled =   
     !(Char.IsWhiteSpace(e.KeyChar))) && (e.Handled = 
     !(Char.IsPunctuation(e.KeyChar))) && (e.Handled = 
     !(Char.IsSymbol(e.KeyChar))) && (e.Handled = !(Char.IsControl(e.KeyChar))))
     {
         e.Handled = true;
     }
}
 

this works perfectly, but does anyone know how to do th eabove in a shorter version.

Cheers,

The above will work for a desktop application.
If you're developing a web application please see the article on how to check if a textbox contains a number.

-Frinny

[LoanB]

Thanks mate

That will be very helpful next week when I start with the WEB stuff.