limit input to numbers?

[marvinklein]

how do i set the properties of a text box so that the user can only enter numbers?
thanks,
marvin

[Lunatic3]

use something like this:

Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress
   If Not Char.IsDigit(e.KeyChar) Then
        e.Handled=True
   End If
End Sub

[MikeStammer]

That way would allow you to check as they were entered. You could also use regular expressions to validate it in the Validating event. If you didnt want to check every character as it is entered, code something up in the validating event (either a RegEx or something else) and if its not a number (IsNumeric returns false is another way to check) then show a msgbox and set cancel = true.

[Pirate]

Originally posted by MikeStammer
That way would allow you to check as they were entered. You could also use regular expressions to validate it in the Validating event. If you didnt want to check every character as it is entered, code something up in the validating event (either a RegEx or something else) and if its not a number (IsNumeric returns false is another way to check) then show a msgbox and set cancel = true.

lol .

I wouldn't bother with RE just to allow numbers . The code lunatic3 posted is good . Another way is here :

Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress
 
        'Numeric keys start with 48 through 52
        'backspace key has the ascii code 8
        'period key has the ascii code 46
 
        Dim KeyAscii As Integer
        KeyAscii = Asc(e.KeyChar)
 
        'only disallow numeric values
        Select Case KeyAscii
            Case Asc("0") To Asc("9")
                'acceptable keystrokes 
                e.Handled = True
                '   Case Asc(".") if you want to disable
                                  'other keys
 
 
                    'e.Handled = True 
            Case Else
                e.Handled = False
        End Select
End Sub

I bet on that .

[powdir]

the only problem i can see here is if the user copies n' pastes a string containing numeric chars directly into the textbox you wish to validate. So i would go with something in the text_changed event or suchlike.

Cheers...

[MikeStammer]

my thoughts exactly! Thats what validate event is for, to validate things!

[Pirate]

Originally posted by MikeStammer
my thoughts exactly! Thats what validate event is for, to validate things!

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