' Set up the conditions for finding the text control.
Dim documentControl As New PropertyCondition( _
AutomationElement.ControlTypeProperty, ControlType.Document)
Dim textPatternAvailable As New PropertyCondition( _
AutomationElement.IsTextPatternAvailableProperty, True)
Dim findControl As New AndCondition(documentControl, textPatternAvailable)

' Get the Automation Element for the first text control found.
' For the purposes of this sample it is sufficient to find the 
' first text control. In other cases there may be multiple text
' controls to sort through.
targetDocument = targetWindow.FindFirst(TreeScope.Descendants, findControl)

' Didn't find a text control.
If targetDocument Is Nothing Then
    targetResult.Content = _
    WPFTarget + " does not contain a Document control type."
    targetResult.Background = Brushes.Salmon
    startWPFTargetButton.IsEnabled = False
    Return
End If

' Get required control patterns 
targetTextPattern = DirectCast( _
targetDocument.GetCurrentPattern(TextPattern.Pattern), TextPattern)

' Didn't find a text control that supports TextPattern.
If targetTextPattern Is Nothing Then
    targetResult.Content = WPFTarget + _
    " does not contain an element that supports TextPattern."
    targetResult.Background = Brushes.Salmon
    startWPFTargetButton.IsEnabled = False
    Return
End If