[RESOLVED] The user should be allowed to enter only these 3 numbers,1, 2, or 3, in a textbox.

[VS2013]

Hi,

The user should be allowed to enter only these 3 numbers,1, 2, or 3, in a textbox. How to restrict him from entering other characters?

Please help.

[OptionBase1]

One option is to sell a specialty keyboard with your software that only has those three keys on it.

Or you could just use a numeric up/down control and set the min value to 1 and the max value to 3.

[.paul.]

Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress
    Dim validChars() As Char = {"1"c, "2"c, "3"c}
    e.Handled = Not (validChars.Contains(e.KeyChar) OrElse Char.IsControl(e.KeyChar))
End Sub

[VS2013]

Private Sub TextBox1_KeyPress(ByVal sender As Object, ByVal e As System.Windows.Forms.KeyPressEventArgs) Handles TextBox1.KeyPress
    Dim validChars() As Char = {"1"c, "2"c, "3"c}
    e.Handled = Not (validChars.Contains(e.KeyChar) OrElse Char.IsControl(e.KeyChar))
End Sub

Thanks for your kind support. Actually, I forgot to mention one thing that the user should enter any single character in that textbox (Ex: 1 or 2 or 3) not 2 characters like 12, 13, 31 etc.

[.paul.]

Thanks for your kind support. Actually, I forgot to mention one thing that the user should enter any single character in that textbox (Ex: 1 or 2 or 3) not 2 characters like 12, 13, 31 etc.

Set your TextBox MaxLength property

[VS2013]

Thanks.