Auto-incrementing Form Fields

When you are working with forms, you save the forms as templates that are used as the basis of new documents in Word. There may be times when you want to add a form field that increments every time you create a new document based on your form template. For instance, you might have a sequence number that you need for a data input form, or you may want to use a form field to indicate an invoice number.

Word does not have any fancy auto-increment fields. However, by combining some of the tools already available in Word, you can create a template and form field to do the trick for you. Start with this VBA macro:

Sub AutoNew()
   ' Exit macro if no fields in document
   If ActiveDocument.FormFields.Count = 0 Then Exit Sub
   ' Create variables.
   Dim OfficeAppName As String
   Dim RegSection As String
   Dim RegKey As String
   Dim FieldObj As Object
   Dim RegValue As Long

   OfficeAppName = "Word 2002"
   RegSection = "UserData"
   RegKey = "Current Counter"
   ' Generate error if form field doesn't exist
   On Error GoTo ErrHandler
   Set FieldObj = ActiveDocument.FormFields("IncField")
   ' Get stored registry value, if any
   RegValue = GetSetting(OfficeAppName, RegSection, RegKey, 0)
   ' If not previously set, set to default
   If RegValue = 0 Then RegValue = 1
   ' Set form field result to stored value
   FieldObj.Result = CStr(RegValue)
   ' Increment and update invoice number
   SaveSetting OfficeAppName, RegSection, RegKey, RegValue + 1
ErrHandler:
   If Err <> 0 Then
      MsgBox Err.Description
   End If
End Sub

This macro should be saved only in the template that you will use to create your forms. The macro must be named AutoNew, so it will run whenever a document is created that is based on the form template. You should also make sure that you have a text form field in your document named IncField, which will display the incremental number. The number is tracked in the Registry so it can be accessed for future forms.

Notice the line in the macro that sets the OfficeAppName variable. In this version of the macro, it is set to the phrase "Word 2002". If you are using a different version of Word, you should modify this line so it refers to your version, such as "Word 2000" or "Word 2007".