Need to include subform fields in "For Each ctl In Me.Controls"

A few days ago, shanesuebsahakarn helped me to come up w/ a great "validation function".

Here's what I have:
- Main form w/ tab control
- Tab control has 3 tabs
- Tab0 and Tab1 have required controls (both textfield and combos); Tab2 doesn't have any required controls at this time
- Tab1 and Tab2 have subforms; each subform will have a single required field (control); Tab0 does not have a subform

Here's what the function does:
- If I do NOT complete all required controls on e.g. tab0 and click on tab1, all required controls on Tab0 are highlighted in yellow; moreover, the function sets focus to the "1st invalid" (no data) control vs. to the "1st control on page" (whether valid or invalid)
- the same process for tab1... if I completed everything on tab0 and then move to tab1 but forget to complete all required controls on tab1, I get the error message when clicking on tab2

Question/Problem:  I need to modify the function (or come up w/ additional code) that will allow me to also highlight a field that resides in a subform.   Does anyone know how to include the highlighting of required controls in a subform?

Thanks,
Tom



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Option Compare Database
Option Explicit
Dim lngTabPage As Long

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Private Sub Form_BeforeUpdate(Cancel As Integer)
   
    Dim ctl As Control
    Dim NotComplete As Boolean
    Dim strControlName As String
    'The global variable "lngTabPage" is declared at the top of the module
    'lngTabPage keeps track of the required controls per tab (tabs 0,1,2 have values: R0, R1, R2)

    'Keeps track of the "next invalid" control (unselected/no data)
    strControlName = ""
   
    NotComplete = False
    For Each ctl In Me.Controls
       If ctl.Tag = "R" & lngTabPage Then
          If (ctl.Value & "") = "" Then
             ctl.BackColor = vbYellow
             NotComplete = True
             If strControlName = "" Then strControlName = ctl.Name
           End If
        End If
    Next
   
    If NotComplete Then
       Cancel = True
       Me!RRISTabControl = lngTabPage
       Me(strControlName).SetFocus
       MsgBox "You must complete the yellow highlighted field!", vbCritical, "Required Data Missing"
    Else
       lngTabPage = Me!RRISTabControl
    End If
End Sub  
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