StrokeCollection.GetIncrementalStrokeHitTester Method

Creates an IncrementalStrokeHitTester that hit tests the StrokeCollection with an erasing path.

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

public IncrementalStrokeHitTester GetIncrementalStrokeHitTester(
	StylusShape eraserShape
)

Parameters

eraserShape
Type: System.Windows.Ink.StylusShape

A StylusShape that specifies the tip of the stylus.

The GetIncrementalStrokeHitTester method returns an IncrementalStrokeHitTester that considers a Stroke to be "hit" when the eraser path intersects it. This is useful for implementing features, such as the ability to erase part of a Stroke. The InkCanvas uses an IncrementalStrokeHitTester when the EditingMode property is set to EraseByPoint.

The following example demonstrates how to get an IncrementalStrokeHitTester that can be used to erase part of a Stroke. To create a control that enables a user to erase ink, see How to: Erase Ink on a Custom Control.

// Prepare to collect stylus packets. Get the  
// IncrementalHitTester from the InkPresenter's  
// StrokeCollection and subscribe to its StrokeHitChanged event. 
protected override void OnStylusDown(StylusDownEventArgs e)
{
    base.OnStylusDown(e);

    EllipseStylusShape eraserTip = new EllipseStylusShape(3, 3, 0);
    eraseTester = 
        presenter.Strokes.GetIncrementalStrokeHitTester(eraserTip);
    eraseTester.StrokeHit += new StrokeHitEventHandler(eraseTester_StrokeHit);
    eraseTester.AddPoints(e.GetStylusPoints(this));

}

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1
Was this page helpful?
(1500 characters remaining)
Thank you for your feedback
Show:
© 2015 Microsoft