TextPatternRange.CompareEndpoints Method

Reference

Definition

Namespace:: System.Windows.Automation.Text

Assembly:: UIAutomationClient.dll

Important

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Returns an Int32 indicating whether two text ranges have identical endpoints.

public:
 int CompareEndpoints(System::Windows::Automation::Text::TextPatternRangeEndpoint endpoint, System::Windows::Automation::Text::TextPatternRange ^ targetRange, System::Windows::Automation::Text::TextPatternRangeEndpoint targetEndpoint);

public int CompareEndpoints (System.Windows.Automation.Text.TextPatternRangeEndpoint endpoint, System.Windows.Automation.Text.TextPatternRange targetRange, System.Windows.Automation.Text.TextPatternRangeEndpoint targetEndpoint);

member this.CompareEndpoints : System.Windows.Automation.Text.TextPatternRangeEndpoint * System.Windows.Automation.Text.TextPatternRange * System.Windows.Automation.Text.TextPatternRangeEndpoint -> int

Public Function CompareEndpoints (endpoint As TextPatternRangeEndpoint, targetRange As TextPatternRange, targetEndpoint As TextPatternRangeEndpoint) As Integer

Parameters

endpoint: TextPatternRangeEndpoint

The Start or End endpoint of the caller.

targetRange: TextPatternRange

The target range for comparison.

targetEndpoint: TextPatternRangeEndpoint

The Start or End endpoint of the target.

Returns

Int32

Returns a negative value if the caller's endpoint occurs earlier in the text than the target endpoint.

Returns zero if the caller's endpoint is at the same location as the target endpoint.

Returns a positive value if the caller's endpoint occurs later in the text than the target endpoint.

Exceptions

ArgumentNullException

If range is a null reference (Nothing in Visual Basic).

ArgumentException

If range is from another container.

Examples

private Int32 CompareRangeEndpoints(AutomationElement target)
{
    // Specify the control type we're looking for, in this case 'Document'
    PropertyCondition cond = new PropertyCondition(AutomationElement.ControlTypeProperty, ControlType.Document);

    // target --> The root AutomationElement.
    AutomationElement textProvider = target.FindFirst(TreeScope.Descendants, cond);

    TextPattern textpatternPattern = textProvider.GetCurrentPattern(TextPattern.Pattern) as TextPattern;

    if (textpatternPattern == null)
    {
        Console.WriteLine("Root element does not contain a descendant that supports TextPattern.");
        return 0;
    }
    TextPatternRange[] currentSelections = textpatternPattern.GetSelection();
    TextPatternRange[] currentVisibleRanges = textpatternPattern.GetVisibleRanges();
    return currentSelections[0].CompareEndpoints(
        TextPatternRangeEndpoint.Start, 
        currentVisibleRanges[0], 
        TextPatternRangeEndpoint.Start);
}

Private Function CompareRangeEndpoints(ByVal target As AutomationElement) As Integer
    ' Specify the control type we're looking for, in this case 'Document'
    Dim cond As PropertyCondition = New PropertyCondition(AutomationElement.ControlTypeProperty, ControlType.Document)

    ' target --> The root AutomationElement.
    Dim textProvider As AutomationElement = target.FindFirst(TreeScope.Descendants, cond)

    Dim textpatternPattern As TextPattern = CType(textProvider.GetCurrentPattern(TextPattern.Pattern), TextPattern)

    If (textpatternPattern Is Nothing) Then
        Console.WriteLine("Root element does not contain a descendant that supports TextPattern.")
        Return Nothing
    End If
    Dim currentSelection As TextPatternRange() = textpatternPattern.GetSelection()
    Dim currentVisibleRanges As TextPatternRange() = textpatternPattern.GetVisibleRanges()
    Return currentSelection(0).CompareEndpoints(TextPatternRangeEndpoint.Start, _
                                         currentVisibleRanges(0), _
                                         TextPatternRangeEndpoint.Start)
End Function

Remarks

By comparing the starting and ending endpoints of the same text range you can identify if a text range is degenerate or if the endpoints are in the order of logical text flow.

Applies to

Jaa