How to undoing a TextBox

[alinagoo]

Hi all.
I wanted to change value of a TextBox to previous value of that TextBox when a user types some special data but i couldn't change value in BeforeUpdate or AfterUpdate Event handler!
Is any special command or method exists to undo only one TextBoxe's value of a form?
Thanks in advanced

[ADezii]

@alinagoo
Let's say that you have a 'Bound' Field on a Form named [Margin]. Let's also suppose that if at any time, a User enters a Margin of > 10 into this Field for an existing Record, you then wish to restore the Original Value of that Field. In the AfterUpdate() Event of the [Margin] Field:

Private Sub Margin_AfterUpdate()
Dim ctlTBox As TextBox
 
Set ctlTBox = Me![Margin]
 
If ctlTBox > 10 Then
  ctlTBox = ctlTBox.OldValue
End If
End Sub

[missinglinq]

What exactly did you try?

Private Sub TextBoxName_AfterUpdate()
 If Me.TextBoxName.Value = "9999" Then
  Me.TextBoxName.Value = Me.TextBoxName.OldValue
 End If
End Sub

should work, replacing 9999 with the triggering value. Omit the quotes, of course, if the value is Numerical instead of Text.

Linq ;0)>

[NeoPa]

I don't know what you tried but cancelling an update if the value doesn't fit is pretty straightforward :

Private Sub YourTextBox_BeforeUpdate(Cancel As Integer)
    If Me.YourTextBox = "Invalid Value" Then Cancel = True
End Sub

[alinagoo]

Thanks you all
But NeoPa's method does not worked properly and the method used by Missinglinq and ADezii with OlaValue property works fine.
Good Luck

[NeoPa]

NeoPa's method should work if done properly. What did you try (This was asked before)?

[alinagoo]

@NeoPa
I used "Cancel = True" in BeforeUpdate Event handler of a TextBox to convert value of that TextBox to previous saved value if newly typed value is not in a valid range but it does not work!

Thank
Good Luck

[NeoPa]

My mistake. The Cancel = True simply stops the cursor leaving the control. Attempting to set the value in a BeforeUpdate() event procedure always triggers an error, so the trick to doing it properly is to use the .Undo() method.

Using ADezii's situation as an example :

Private Sub Margin_BeforeUpdate(Cancel As Integer)
    With Me.Margin
        If .Value > 10 Then
            Call .Undo
            Cancel = True
        End If
    End With
End Sub

This leaves the cursor in the control, as well as reverting the data to that before any changes were attempted.