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IncrementalStrokeHitTester Class

Dynamically hit tests a stroke with an eraser path.

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

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

The IncrementalStrokeHitTester hit tests strokes by determining when a eraser path intersects that stroke. Use the AddPoints(Point) method in the stylus events to add the points to the IncrementalStrokeHitTester. When the points added to the IncrementalStrokeHitTester intersect a Stroke, the IncrementalStrokeHitTester raises the StrokeHit event.

The following example demonstrates how to dynamically erase a portion of a Stroke. To create a control that enables a user to erase ink, see How to: Erase Ink on a Custom Control.

// When the stylus intersects a stroke, erase that part of 
// the stroke.  When the stylus dissects a stoke, the  
// Stroke.Erase method returns a StrokeCollection that contains 
// the two new strokes. 
void eraseTester_StrokeHit(object sender,
    StrokeHitEventArgs args)
    StrokeCollection eraseResult =
    StrokeCollection strokesToReplace = new StrokeCollection();

    // Replace the old stroke with the new one. 
    if (eraseResult.Count > 0)
        presenter.Strokes.Replace(strokesToReplace, eraseResult);



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