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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

The IncrementalLassoHitTester type exposes the following members.

Public propertyIsValidGets whether the IncrementalHitTester is hit testing. (Inherited from IncrementalHitTester.)

Public methodAddPointAdds a Point to the IncrementalHitTester. (Inherited from IncrementalHitTester.)
Public methodAddPoints(IEnumerable<Point>)Adds points to the IncrementalHitTester. (Inherited from IncrementalHitTester.)
Public methodAddPoints(StylusPointCollection)Adds the specified StylusPoint objects to the IncrementalHitTester. (Inherited from IncrementalHitTester.)
Protected methodAddPointsCoreInfrastructure. Adds points to the IncrementalHitTester. (Overrides IncrementalHitTester.AddPointsCore(IEnumerable<Point>).)
Public methodEndHitTestingReleases resources used by the IncrementalHitTester. (Inherited from IncrementalHitTester.)
Public methodEquals(Object)Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected methodFinalizeAllows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public methodGetHashCodeServes as a hash function for a particular type. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Protected methodMemberwiseCloneCreates a shallow copy of the current Object. (Inherited from Object.)
Protected methodOnSelectionChangedInfrastructure. Raises the SelectionChanged event.
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)

Public eventSelectionChangedOccurs when the lasso path selects or unselects an ink Stroke.

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;

.NET Framework

Supported in: 4, 3.5, 3.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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

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