You can open the property ValidationGroupin your UserControl, which you would set from the page. This value must be stored in the ViewState, so that each instance of UserControl will receive different ValidationGroups (if your page assigns different).
For instance:
Public Property ValidationGroup() As String
Get
Return CStr(ViewState("ValidationGroup"))
End Get
Set(ByVal value As String)
SetValidationGroupOnChildren(Me, value)
ViewState("ValidationGroup") = value
End Set
End Property
Private Sub SetValidationGroupOnChildren(ByVal parent As Control, ByVal validationGroup As String)
For Each ctrl As Control In parent.Controls
If TypeOf ctrl Is BaseValidator Then
CType(ctrl, BaseValidator).ValidationGroup = validationGroup
ElseIf TypeOf ctrl Is IButtonControl Then
CType(ctrl, IButtonControl).ValidationGroup = validationGroup
ElseIf ctrl.HasControls() And ctrl.Visible = True Then
SetValidationGroupOnChildren(ctrl, validationGroup)
End If
Next
End Sub
ValidationGroups UserControl, , . , UserControl ( ) ClientID ValidationGroup . , , PreRender.