Ensuring Proper Data Entry

[skg]

I have a purchase order form with a subform for line item details. I want to put a Total field on the form that must equal the total of the line item details.

I want an error message to pop up if the amounts are not equal and keep the information from saving unless they are equal.



Any ideas where to start?

[RuralGuy]

Is this just a double check? You would catch this issue in the BeforeUpdate event of the MainForm. Does that help?

[skg]

Yes it is a double check, but I am not sure of how to write the code.

[RuralGuy]

You would put a TextBox in the Footer of the SubForm (which does not display when the form is in Continuous Form mode) that sums the field you want. Then compare this control with the one on the mainForm in the BeforeUpdate event of the MainForm.

[skg]

Please pardon my ignorance. All of what you have said makes sense, but I still don't understand what code to put in the BeforeUpdate event.

[RuralGuy]

Something like:

Private Sub Form_BeforeUpdate(Cancel As Integer)
   If Me.MainFormControlName <> Me.SubFormControlName.Form.SummingControlName Then
      MsgBox "Does not balance - NOT saving!", vbCritical + vbOKOnly
      Cancel = True
   End If
End Sub

...using your ControlNames of course!