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IncrementalLassoHitTester Class

Dynamically hit tests a Stroke with a lasso.

Namespace:  System.Windows.Ink
Assembly:  PresentationCore (in PresentationCore.dll)

public class IncrementalLassoHitTester : IncrementalHitTester
You cannot directly create an instance of this class in XAML.

The IncrementalLassoHitTester hit tests strokes by determining whether a lasso path surrounds it. Use the AddPoints(Point) method in the stylus events to add the points to the IncrementalLassoHitTester. When the points added to the IncrementalLassoHitTester selects or unselects a Stroke, the IncrementalLassoHitTester raises the SelectionChanged event

The following example demonstrates how to dynamically select strokes in a custom control. For the entire sample, see How to: Select Ink from a Custom Control

void selectionTester_SelectionChanged(object sender,
    LassoSelectionChangedEventArgs args)
    // Change the color of all selected strokes to red. 
    foreach (Stroke selectedStroke in args.SelectedStrokes)
        selectedStroke.DrawingAttributes.Color = Colors.Red;


    // Change the color of all unselected strokes to  
    // their original color. 
    foreach (Stroke unselectedStroke in args.DeselectedStrokes)
        unselectedStroke.DrawingAttributes.Color = inkDA.Color;


Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0