StrokeCollection.HitTest Method

Reference

Definition

Namespace:: System.Windows.Ink

Assembly:: PresentationCore.dll

Important

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Returns a collection of strokes contained within the specified area.

Overloads

HitTest(Rect, Int32)	Returns a collection of strokes that have at least the specified percentage of length within the specified rectangle.
HitTest(Point, Double)	Returns a collection of strokes that intersect the specified area.
HitTest(IEnumerable<Point>, StylusShape)	Returns a collection of strokes that intersect with the specified path.
HitTest(IEnumerable<Point>, Int32)	Returns a collection of strokes that have at least the specified percentage of length within the specified area.
HitTest(Point)	Returns a collection of strokes that intersect the specified point.

HitTest(Rect, Int32)

Returns a collection of strokes that have at least the specified percentage of length within the specified rectangle.

public:
 System::Windows::Ink::StrokeCollection ^ HitTest(System::Windows::Rect bounds, int percentageWithinBounds);

public System.Windows.Ink.StrokeCollection HitTest (System.Windows.Rect bounds, int percentageWithinBounds);

member this.HitTest : System.Windows.Rect * int -> System.Windows.Ink.StrokeCollection

Public Function HitTest (bounds As Rect, percentageWithinBounds As Integer) As StrokeCollection

Parameters

bounds: Rect

A Rect that specifies the bounds to be hit tested.

percentageWithinBounds: Int32

The minimum required length of a Stroke that must exist within bounds for it to be considered hit.

Returns

StrokeCollection

A StrokeCollection that has strokes with at least the specified percentage within the Rect.

Examples

The following example erases the strokes that are at least 50% within the bounds of the Rect. This example assumes that there is an InkPresenter called presenter.

Rect rect = new Rect(100, 100, 200, 200);
StrokeCollection strokes = presenter.Strokes.HitTest(rect, 50);

presenter.Strokes.Remove(strokes);

Dim rect As Rect = New Rect(100, 100, 200, 200)
Dim strokes As StrokeCollection = presenter.Strokes.HitTest(rect, 50)

presenter.Strokes.Remove(strokes)

Applies to

HitTest(Point, Double)

Returns a collection of strokes that intersect the specified area.

public:
 System::Windows::Ink::StrokeCollection ^ HitTest(System::Windows::Point point, double diameter);

public System.Windows.Ink.StrokeCollection HitTest (System.Windows.Point point, double diameter);

member this.HitTest : System.Windows.Point * double -> System.Windows.Ink.StrokeCollection

Public Function HitTest (point As Point, diameter As Double) As StrokeCollection

Parameters

point: Point

The Point to hit test.

diameter: Double

The size of the area around the Point to hit test.

Returns

StrokeCollection

A collection of Stroke objects that intersect the specified point.

Examples

The following example demonstrates how to get the strokes that intersect the specified Point. This example assumes that there is an InkPresenter called presenter.

// Change the color of all the strokes at the specified position.
public void SelectStrokes(Point position)
{
    StrokeCollection selected = presenter.Strokes.HitTest(position, 5);

    foreach (Stroke s in selected)
    {
        s.DrawingAttributes.Color = Colors.Purple;
    }
}

' Change the color of all the strokes at the specified position.
Public Sub SelectStrokes(ByVal position As Point)

    Dim selected As StrokeCollection = presenter.Strokes.HitTest(position, 5)

    Dim s As Stroke
    For Each s In selected
        s.DrawingAttributes.Color = Colors.Purple
    Next s

End Sub

Applies to

HitTest(IEnumerable<Point>, StylusShape)

Returns a collection of strokes that intersect with the specified path.

public:
 System::Windows::Ink::StrokeCollection ^ HitTest(System::Collections::Generic::IEnumerable<System::Windows::Point> ^ path, System::Windows::Ink::StylusShape ^ stylusShape);

public System.Windows.Ink.StrokeCollection HitTest (System.Collections.Generic.IEnumerable<System.Windows.Point> path, System.Windows.Ink.StylusShape stylusShape);

member this.HitTest : seq<System.Windows.Point> * System.Windows.Ink.StylusShape -> System.Windows.Ink.StrokeCollection

Public Function HitTest (path As IEnumerable(Of Point), stylusShape As StylusShape) As StrokeCollection

Parameters

path: IEnumerable<Point>

An array to type Point that represents the path to be hit tested.

stylusShape: StylusShape

The StylusShape that specifies the shape of eraserPath.

Returns

StrokeCollection

A StrokeCollection of strokes that intersect with path.

Examples

The following example changes the color of all the strokes that intersect the path that is created by the Point array. This example assumes that there is an InkPresenter called presenter.

private void HitTestWithEraser(Point[] points)
{
    RectangleStylusShape eraser = new RectangleStylusShape(3, 3, 0);

    StrokeCollection strokes = presenter.Strokes.HitTest(points, eraser);

    foreach (Stroke s in strokes)
    {
        s.DrawingAttributes.Color = Colors.Purple;
    }
}

Private Sub HitTestWithEraser(ByVal points() As Point)
    Dim eraser As RectangleStylusShape = New RectangleStylusShape(3, 3, 0)

    Dim strokes As StrokeCollection = presenter.Strokes.HitTest(points, eraser)

    Dim s As Stroke
    For Each s In strokes
        s.DrawingAttributes.Color = Colors.Purple
    Next
End Sub

Applies to

HitTest(IEnumerable<Point>, Int32)

Returns a collection of strokes that have at least the specified percentage of length within the specified area.

public:
 System::Windows::Ink::StrokeCollection ^ HitTest(System::Collections::Generic::IEnumerable<System::Windows::Point> ^ lassoPoints, int percentageWithinLasso);

public System.Windows.Ink.StrokeCollection HitTest (System.Collections.Generic.IEnumerable<System.Windows.Point> lassoPoints, int percentageWithinLasso);

member this.HitTest : seq<System.Windows.Point> * int -> System.Windows.Ink.StrokeCollection

Public Function HitTest (lassoPoints As IEnumerable(Of Point), percentageWithinLasso As Integer) As StrokeCollection

Parameters

lassoPoints: IEnumerable<Point>

An array of type Point that represents the bounds of the area to be hit tested.

percentageWithinLasso: Int32

The acceptable length of the Stroke, as a percentage, for lassoPoints to contain.

Returns

StrokeCollection

A StrokeCollection that has strokes with at least the specified percentage within the Point array.

Exceptions

ArgumentNullException

lassoPoints is null.

-or-

percentageWithinLasso is null.

ArgumentException

lassoPoints contains an empty array.

ArgumentOutOfRangeException

percentageWithinLasso is less than 0 or greater than 100.

Examples

The following example demonstrates how to remove all strokes that are at least 80 percent within the specified lasso from a StrokeCollection. This is useful when a custom control enables the user to select ink with a lasso. To create a control that enables a user to select ink with a lasso, see How to: Select Ink from a Custom Control.

// Remove the strokes within the lasso from the InkPresenter
public void RemoveStrokes(Point[] lasso)
{
    StrokeCollection strokes = presenter.Strokes.HitTest(lasso, 80);

    presenter.Strokes.Remove(strokes);
}

' Remove the strokes within the lasso from the InkPresenter
Public Sub RemoveStrokes(ByVal lasso As Point())

    If lasso Is Nothing Then
        Return
    End If

    Dim strokes As StrokeCollection = _
        presenter.Strokes.HitTest(lasso, 80)

    presenter.Strokes.Remove(strokes)

End Sub

Applies to

HitTest(Point)

Returns a collection of strokes that intersect the specified point.

public:
 System::Windows::Ink::StrokeCollection ^ HitTest(System::Windows::Point point);

public System.Windows.Ink.StrokeCollection HitTest (System.Windows.Point point);

member this.HitTest : System.Windows.Point -> System.Windows.Ink.StrokeCollection

Public Function HitTest (point As Point) As StrokeCollection

Parameters

point: Point

The point to hit test.

Returns

StrokeCollection

A collection of Stroke objects that intersect the specified point.

Examples

The following example demonstrates how to get the strokes that intersect the specified Point. This example assumes that there is an InkPresenter called presenter.

// Change the color of all the strokes at the specified position.
public void SelectStrokes(Point position)
{
    StrokeCollection selected = presenter.Strokes.HitTest(position, 5);

    foreach (Stroke s in selected)
    {
        s.DrawingAttributes.Color = Colors.Purple;
    }
}

' Change the color of all the strokes at the specified position.
Public Sub SelectStrokes(ByVal position As Point)

    Dim selected As StrokeCollection = presenter.Strokes.HitTest(position, 5)

    Dim s As Stroke
    For Each s In selected
        s.DrawingAttributes.Color = Colors.Purple
    Next s

End Sub

Applies to

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StrokeCollection.HitTest Method

Definition

Overloads

HitTest(Rect, Int32)

Parameters

Returns

Examples

Applies to

HitTest(Point, Double)

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Returns

Examples

Applies to

HitTest(IEnumerable<Point>, StylusShape)

Parameters

Returns

Examples

Applies to

HitTest(IEnumerable<Point>, Int32)

Parameters

Returns

Exceptions

Examples

Applies to

HitTest(Point)

Parameters

Returns

Examples

Applies to

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