Owner's manual

DOKuStar Validation for Ascent Capture Page • 98
Not Restore Old Contents
When a scripting routine returns False in the OnFieldChanging event, the original contents of the field
(before the user changed it) is restored.
Sometimes however it might be better to keep what the user typed in, but still stay in the field and display an error
message. This might be suitable for larger texts, where the user just made a spelling mistake. It is better then to let
him correct what he typed than to let him enter it completely once again.
This can be achieved the following way:
- Return
True in the OnFieldChanging event
- Return
False in the OnFieldDeactivating event
The
OnFieldChanging will determine that the user typed in something wrong, but accept the field anyway.
Thus, the field really gets the new value. The
OnFieldDeactivating then will prevent the user from leaving the
field.
The fact that the field’s contents was wrong, must somehow be transported from the
OnFieldChanging event to
the
OnFieldDeactivating event: The OnFieldDeactivating cannot determine it on its own, because the
field’s contents already changed. The best way to do it is to add a
UserData to the field:
Option Explicit
Dim WithEvents Field As FieldType
Private Sub Application_OnProjectLoaded(ByVal App As Application)
Set Field =
App.Project.DataSet.Schema.DocumentTypes("InvoiceTable").FieldTypes("TotalAmount")
End Sub
Private Function Field_OnFieldChanging(ByVal Field As Field, ByVal SubField As Field, _
ByVal VerifyEventArgs As VerifyEventArgs) As Boolean
Field_OnFieldChanging = True
'* reset old contents
If Field.UserData.HasValue("ErrorText") Then
Field.UserData.RemoveValue ("ErrorText")
End If
If Val(Field.Value) <= 0 Then
Field.UserData.Value("ErrorText") = "TotalAmount must be positiv"
End If
End Function
Private Function Field_OnFieldDeactivating(ByVal Field As Field, ByVal NextField As Field) As
Boolean
Field_OnFieldDeactivating = True
If Field.UserData.HasValue("ErrorText") Then
MsgBox Field.UserData.Value("ErrorText")
Field_OnFieldDeactivating = False
End If
End Function
Note that you cannot use the
OnFieldChanged instead of the OnFieldChanging event for this purpose,
because this event will be fired after the
OnFieldDeactivating!