Help with validation problem

[dwd3773]

I'm trying to get a validation of a text box to where if the information is not letters then it will display a error message. I know how to get the error message, but I dont dont know how to do a validation with letters. I know how to do it with number but not letters. Please help. Thanks.

[fplesco]

I'm trying to get a validation of a text box to where if the information is not letters then it will display a error message. I know how to get the error message, but I dont dont know how to do a validation with letters. I know how to do it with number but not letters. Please help. Thanks.

Hi dwd3773 -

You may try these codes below

Const strAlphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
Private Sub cmdValidate_Click()
    If InvalidTextboxInput = True Then
        MsgBox "Textbox contains invalid character.", vbExclamation
    Else
        MsgBox "Valid textbox content.", vbInformation
    End If
End Sub

Private Function InvalidTextboxInput() As Boolean
    For i = 1 To Len(TextBox1.Text)
        If InStr(strAlphabet, UCase(Mid(TextBox1.Text, i, 1))) < 1 Then
            InvalidTextboxInput = True
            Exit For
        End If
    Next i
End Function

Godspeed!

[Killer42]

I'm trying to get a validation of a text box ...

Quick question - what version of VB are you using?

Oh, and another question - have you considered using a masked edit control rather than a textbox? The masked edit control gives you more control over the format of the input.

[dwd3773]

No, I haven't thought of using one of those. I have strict guideline from my customer as to what they want, but I've never really validated letters only numbers. I 'm using Microsoft Visual Studio 2005.

[Killer42]

No, I haven't thought of using one of those. I have strict guideline from my customer as to what they want, but I've never really validated letters only numbers. I 'm using Microsoft Visual Studio 2005.

Fair enough.

You might as well go with the routine that fplesco provided. It looks as though it will work. One small change I would recommend, though. That is to have it accept the textbox (or just the text) as a parameter, so it's more widely applicable. Seems as though it would make a useful public function to add to your tool kit.

[fplesco]

Fair enough.

You might as well go with the routine that fplesco provided. It looks as though it will work. One small change I would recommend, though. That is to have it accept the textbox (or just the text) as a parameter, so it's more widely applicable. Seems as though it would make a useful public function to add to your tool kit.

[That is to have it accept the textbox (or just the text) as a parameter, so it's more widely applicable]

Good point Killer42. Thanks.

[Killer42]

Good point Killer42. Thanks.

I think it's a good general technique to try and write all one's routines so they're reusable. Though of course there are other considerations, such as performance.

(And of course, being so disorganised, I can never find them again later, anyway. But my intentions are good.)