Kofax DOKuStar Validation - Manual (Page 36)

DOKuStar Validation Programming Manual Page • 32
Private Sub Application_OnProjectLoaded(ByVal App As Application)
Set Amount = App.Project.DataSet.Schema.DocumentTypes("Invoice").FieldTypes("Amount")
End Sub
This subroutine will be called when the project is loaded. The only thing that is done here is that you assign the
variable
Amount , which you defined above, to the right field type: set to the FieldType Amount on the
DocumentType Invoice .
Private Function Amount_OnFieldChanging(ByVal Field As Field, ByVal SubField As Field, ByVal
VerifyEventArgs As VerifyEventArgs) As Boolean
Defining this function enables to catch the FieldChanging event for the amount field:
Whenever the user changes the amount on an invoice, this function will be called and gets an object Field as the
first parameter, which is the field itself. This object has the type Field , which is a notion from the Data part of the
DataSet .
The function is expected to return a boolean value; when returning False , the change is aborted, i.e. the old value
(before the user typed his changes) is restored and the focus stays on this field. When returning True , the changes
are accepted, and the focus usually moves to the next field (“Usually” means: With respect to filters, see separate
chapter).
Amount_OnFieldChanging = True 'Preset return value
The boolean return value is preset to True.
If Val(Field.Value) > 1000 Then
Now take the Field received as a parameter and determine the field’s value. Since a value of a field is always a
string, the Val function must be used to convert to a double integer.
If MsgBox("You entered a value > 1000. Please Confirm.", vbOKCancel) = vbCancel Then
Amount_OnFieldChanging = False 'User clicked cancel, so stay in the field
End If
Open the message box. If the user hits Cancel , set the return value to False , thus aborting the change and
restoring the old contents.
Before getting more into the details, here is a second way of solving the same problem:
Dim WithEvents ctrl As Controller
Private Sub Application_OnProjectLoaded(ByVal App As Application)
Set ctrl = App.Project.DataSet.Controller
End Sub
Private Function ctrl_OnFieldChanging(ByVal Controller As Controller, ByVal Field As Field, ByVal
SubField As Field, ByVal VerifyEventArgs As VerifyEventArgs) As Boolean
ctrl_OnFieldChanging = True 'Preset return value
If Field.Document.Name = "Invoice" And Field.Name = "Amount" Then
If Val(Field.Value) > 1000 Then
If MsgBox("You entered a value > 1000. Please Confirm.", vbOKCancel) = vbCancel Then
ctrl_OnFieldChanging = False 'User clicked cancel, so stay in the field
End If
End If
End If
End Function
This code does the same as the one above, but with a different approach to the problem. Looking at the differences:
In the first line, a variable of the Controller type is defined, and then set to ... Dataset.Controller when the
project is loaded. The Controller is a central object that gets events for every field and document. The outcome here
is an event for every field, no matter which document type and field type.