EllipseGeometry Class

.NET Framework (current version)

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Represents the geometry of a circle or ellipse.

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

Inheritance Hierarchy

System.Object
System.Windows.Threading.DispatcherObject
System.Windows.DependencyObject
System.Windows.Freezable
System.Windows.Media.Animation.Animatable
System.Windows.Media.Geometry
System.Windows.Media.EllipseGeometry

Syntax

C++

public sealed class EllipseGeometry : Geometry

Constructors

	Name	Description
	EllipseGeometry()	Initializes a new instance of the EllipseGeometry class.
	EllipseGeometry(Point, Double, Double)	Initializes a new instance of the EllipseGeometry class as an ellipse that has a specified center location, x radius, and y radius.
	EllipseGeometry(Point, Double, Double, Transform)	Initializes a new instance of the EllipseGeometry class that has the specified position, size, and transformation.
	EllipseGeometry(Rect)	Initializes a new instance of the EllipseGeometry class that has a horizontal diameter equal to the width of the passed Rect, a vertical diameter equal to the length of the passed Rect, and a center point location equal to the center of the passed Rect.

Properties

	Name	Description
	Bounds	Gets a Rect that represents the bounding box of this EllipseGeometry. This method does not consider the extra area potentially added by a stroke. (Overrides Geometry.Bounds.)
	CanFreeze	Gets a value that indicates whether the object can be made unmodifiable. (Inherited from Freezable.)
	Center	Gets or sets the center point of the EllipseGeometry.
	DependencyObjectType	Gets the DependencyObjectType that wraps the CLR type of this instance. (Inherited from DependencyObject.)
	Dispatcher	Gets the Dispatcher this DispatcherObject is associated with. (Inherited from DispatcherObject.)
	HasAnimatedProperties	Gets a value that indicates whether one or more AnimationClock objects is associated with any of this object's dependency properties.(Inherited from Animatable.)
	IsFrozen	Gets a value that indicates whether the object is currently modifiable. (Inherited from Freezable.)
	IsSealed	Gets a value that indicates whether this instance is currently sealed (read-only).(Inherited from DependencyObject.)
	RadiusX	Gets or sets the x-radius value of the EllipseGeometry.
	RadiusY	Gets or sets the y-radius value of the EllipseGeometry.
	Transform	Gets or sets the Transform object applied to a Geometry. (Inherited from Geometry.)

Methods

	Name	Description
	ApplyAnimationClock(DependencyProperty, AnimationClock)	Applies an AnimationClock to the specified DependencyProperty. If the property is already animated, the SnapshotAndReplace handoff behavior is used.(Inherited from Animatable.)
	ApplyAnimationClock(DependencyProperty, AnimationClock, HandoffBehavior)	Applies an AnimationClock to the specified DependencyProperty. If the property is already animated, the specified HandoffBehavior is used.(Inherited from Animatable.)
	BeginAnimation(DependencyProperty, AnimationTimeline)	Applies an animation to the specified DependencyProperty. The animation is started when the next frame is rendered. If the specified property is already animated, the SnapshotAndReplace handoff behavior is used.(Inherited from Animatable.)
	BeginAnimation(DependencyProperty, AnimationTimeline, HandoffBehavior)	Applies an animation to the specified DependencyProperty. The animation is started when the next frame is rendered. If the specified property is already animated, the specified HandoffBehavior is used. (Inherited from Animatable.)
	CheckAccess()	Determines whether the calling thread has access to this DispatcherObject.(Inherited from DispatcherObject.)
	ClearValue(DependencyProperty)	Clears the local value of a property. The property to be cleared is specified by a DependencyProperty identifier. (Inherited from DependencyObject.)
	ClearValue(DependencyPropertyKey)	Clears the local value of a read-only property. The property to be cleared is specified by a DependencyPropertyKey. (Inherited from DependencyObject.)
	Clone()	Creates a modifiable clone of this EllipseGeometry, making deep copies of this object's values. When copying dependency properties, this method copies resource references and data bindings (but they might no longer resolve) but not animations or their current values.
	CloneCurrentValue()	Creates a modifiable clone of this EllipseGeometry object, making deep copies of this object's current values. Resource references, data bindings, and animations are not copied, but their current values are.
	CoerceValue(DependencyProperty)	Coerces the value of the specified dependency property. This is accomplished by invoking any CoerceValueCallback function specified in property metadata for the dependency property as it exists on the calling DependencyObject.(Inherited from DependencyObject.)
	Equals(Object)	Determines whether a provided DependencyObject is equivalent to the current DependencyObject.(Inherited from DependencyObject.)
	FillContains(Geometry)	Indicates whether the current geometry completely contains the specified Geometry.(Inherited from Geometry.)
	FillContains(Geometry, Double, ToleranceType)	Indicates whether the current geometry contains the specified Geometry, given the specified margin of error.(Inherited from Geometry.)
	FillContains(Point)	Indicates whether the geometry contains the specified Point.(Inherited from Geometry.)
	FillContains(Point, Double, ToleranceType)	Indicates whether the geometry contains the specified Point, given the specified margin of error.(Inherited from Geometry.)
	FillContainsWithDetail(Geometry)	Returns a value that describes the intersection between the current geometry and the specified geometry.(Inherited from Geometry.)
	FillContainsWithDetail(Geometry, Double, ToleranceType)	Returns a value that describes the intersection between the current geometry and the specified geometry, given the specified margin of error.(Inherited from Geometry.)
	Freeze()	Makes the current object unmodifiable and sets its IsFrozen property to true. (Inherited from Freezable.)
	GetAnimationBaseValue(DependencyProperty)	Returns the non-animated value of the specified DependencyProperty.(Inherited from Animatable.)
	GetArea()	Gets the area of the filled region of the Geometry object. (Inherited from Geometry.)
	GetArea(Double, ToleranceType)	Gets the area of this EllipseGeometry. (Overrides Geometry.GetArea(Double, ToleranceType).)
	GetAsFrozen()	Creates a frozen copy of the Freezable, using base (non-animated) property values. Because the copy is frozen, any frozen sub-objects are copied by reference. (Inherited from Freezable.)
	GetCurrentValueAsFrozen()	Creates a frozen copy of the Freezable using current property values. Because the copy is frozen, any frozen sub-objects are copied by reference.(Inherited from Freezable.)
	GetFlattenedPathGeometry()	Gets a PathGeometry that is a polygonal approximation of the Geometry object. (Inherited from Geometry.)
	GetFlattenedPathGeometry(Double, ToleranceType)	Gets a PathGeometry, within the specified tolerance, that is a polygonal approximation of the Geometry object. (Inherited from Geometry.)
	GetHashCode()	Gets a hash code for this DependencyObject.(Inherited from DependencyObject.)
	GetLocalValueEnumerator()	Creates a specialized enumerator for determining which dependency properties have locally set values on this DependencyObject. (Inherited from DependencyObject.)
	GetOutlinedPathGeometry()	Gets a PathGeometry that is a simplified outline of the filled region of the Geometry. (Inherited from Geometry.)
	GetOutlinedPathGeometry(Double, ToleranceType)	Gets a PathGeometry, within the specified tolerance, that is a simplified outline of the filled region of the Geometry. (Inherited from Geometry.)
	GetRenderBounds(Pen)	Returns an axis-aligned rectangle that is exactly large enough to contain the geometry after it has been outlined with the specified Pen. (Inherited from Geometry.)
	GetRenderBounds(Pen, Double, ToleranceType)	Returns an axis-aligned rectangle that is exactly large enough to contain the geometry after it has been outlined with the specified Pen, given the specified tolerance factor.(Inherited from Geometry.)
	GetType()	Gets the Type of the current instance.(Inherited from Object.)
	GetValue(DependencyProperty)	Returns the current effective value of a dependency property on this instance of a DependencyObject. (Inherited from DependencyObject.)
	GetWidenedPathGeometry(Pen)	Gets a PathGeometry that is the shape defined by the stroke on the Geometry produced by the specified Pen. (Inherited from Geometry.)
	GetWidenedPathGeometry(Pen, Double, ToleranceType)	Gets a PathGeometry that is the shape defined by the stroke on the Geometry produced by the specified Pen, given the specified tolerance factor.(Inherited from Geometry.)
	InvalidateProperty(DependencyProperty)	Re-evaluates the effective value for the specified dependency property(Inherited from DependencyObject.)
	IsEmpty()	Determines whether this EllipseGeometry object is empty. (Overrides Geometry.IsEmpty().)
	MayHaveCurves()	Determines whether this EllipseGeometry object can have curved segments. (Overrides Geometry.MayHaveCurves().)
	ReadLocalValue(DependencyProperty)	Returns the local value of a dependency property, if it exists. (Inherited from DependencyObject.)
	SetCurrentValue(DependencyProperty, Object)	Sets the value of a dependency property without changing its value source. (Inherited from DependencyObject.)
	SetValue(DependencyProperty, Object)	Sets the local value of a dependency property, specified by its dependency property identifier. (Inherited from DependencyObject.)
	SetValue(DependencyPropertyKey, Object)	Sets the local value of a read-only dependency property, specified by the DependencyPropertyKey identifier of the dependency property. (Inherited from DependencyObject.)
	ShouldSerializeProperty(DependencyProperty)	Returns a value that indicates whether serialization processes should serialize the value for the provided dependency property.(Inherited from DependencyObject.)
	ShouldSerializeTransform()	Gets a value that indicates whether the value of the Transform property should be serialized.(Inherited from Geometry.)
	StrokeContains(Pen, Point)	Determines whether the specified Point is contained in the stroke produced by applying the specified Pen to the geometry. (Inherited from Geometry.)
	StrokeContains(Pen, Point, Double, ToleranceType)	Determines whether the specified Point is contained in the stroke produced by applying the specified Pen to the geometry, given the specified margin of error.(Inherited from Geometry.)
	StrokeContainsWithDetail(Pen, Geometry)	Returns a value that describes the intersection between the specified Geometry and the stroke created by applying the specified Pen to the current geometry.(Inherited from Geometry.)
	StrokeContainsWithDetail(Pen, Geometry, Double, ToleranceType)	Gets a value that describes the intersection between the specified Geometry and the stroke created by applying the specified Pen to the current geometry, given the specified margin of error.(Inherited from Geometry.)
	ToString()	Creates a string representation of the object based on the current culture. (Inherited from Geometry.)
	ToString(IFormatProvider)	Creates a string representation of the object using the specified culture-specific formatting information. (Inherited from Geometry.)
	VerifyAccess()	Enforces that the calling thread has access to this DispatcherObject.(Inherited from DispatcherObject.)

Fields

	Name	Description
	CenterProperty	Identifies the Center dependency property.
	RadiusXProperty	Identifies the RadiusX dependency property.
	RadiusYProperty	Identifies the RadiusY dependency property.

Events

	Name	Description
	Changed	Occurs when the Freezable or an object it contains is modified. (Inherited from Freezable.)

Explicit Interface Implementations

	Name	Description
	IFormattable.ToString(String, IFormatProvider)	Formats the value of the current instance using the specified format.(Inherited from Geometry.)

Use the EllipseGeometry class with a Path element or a GeometryDrawing to draw an ellipse, or with the Clip property of a UIElement to define an elliptical clip region. The EllipseGeometry class also has many other uses. For more information about EllipseGeometry, see Geometry Overview.

EllipseGeometry Compared to Ellipse

The Ellipse class has a Fill, Stroke, and other rendering properties that EllipseGeometry lacks. The Ellipse class is a FrameworkElement and therefore participates in the layout system; it can be used as the content of any element that supports UIElement children.

The EllipseGeometry class, on the other hand, simply defines the geometry of an ellipse, and cannot render itself. Because of its simplicity, it has a wider range of uses.

Freezable Features

An EllipseGeometry is a type of Freezable object and therefore can be frozen to improve performance. For information about Freezable features, such as freezing and cloning, see Freezable Objects Overview.

Examples

The following example uses two EllipseGeometry objects to define the contents of a GeometryDrawing. This example produces the following output:

Two EllipseGeometry objects

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;

namespace SDKSample
{
    public class GeometryDrawingExample : Page
    {
        public GeometryDrawingExample()
        {

            //
            // Create the Geometry to draw.
            //
            GeometryGroup ellipses = new GeometryGroup();
            ellipses.Children.Add(
                new EllipseGeometry(new Point(50,50), 45, 20)
                );
            ellipses.Children.Add(
                new EllipseGeometry(new Point(50, 50), 20, 45)
                );


            //
            // Create a GeometryDrawing.
            //
            GeometryDrawing aGeometryDrawing = new GeometryDrawing();
            aGeometryDrawing.Geometry = ellipses;

            // Paint the drawing with a gradient.
            aGeometryDrawing.Brush = 
                new LinearGradientBrush(
                    Colors.Blue, 
                    Color.FromRgb(204,204,255), 
                    new Point(0,0), 
                    new Point(1,1));

            // Outline the drawing with a solid color.
            aGeometryDrawing.Pen = new Pen(Brushes.Black, 10);

            //
            // Use a DrawingImage and an Image control
            // to display the drawing.
            //
            DrawingImage geometryImage = new DrawingImage(aGeometryDrawing);

            // Freeze the DrawingImage for performance benefits.
            geometryImage.Freeze();

            Image anImage = new Image();
            anImage.Source = geometryImage;
            anImage.Stretch = Stretch.None;
            anImage.HorizontalAlignment = HorizontalAlignment.Left;

            //
            // Place the image inside a border and
            // add it to the page.
            //
            Border exampleBorder = new Border();
            exampleBorder.Child = anImage;
            exampleBorder.BorderBrush = Brushes.Gray;
            exampleBorder.BorderThickness = new Thickness(1);
            exampleBorder.HorizontalAlignment = HorizontalAlignment.Left;
            exampleBorder.VerticalAlignment = VerticalAlignment.Top;
            exampleBorder.Margin = new Thickness(10);

            this.Margin = new Thickness(20);
            this.Background = Brushes.White;
            this.Content = exampleBorder;
        }

    }
}

XAML

<Page 
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  xmlns:PresentationOptions="http://schemas.microsoft.com/winfx/2006/xaml/presentation/options" 
  xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
  mc:Ignorable="PresentationOptions"
  Margin="20" Background="White">

  <Border BorderBrush="Gray" BorderThickness="1" 
    HorizontalAlignment="Left" VerticalAlignment="Top"
    Margin="10">
    <Image Stretch="None" HorizontalAlignment="Left">
      <Image.Source>
        <DrawingImage PresentationOptions:Freeze="True">
          <DrawingImage.Drawing>

            <GeometryDrawing>
              <GeometryDrawing.Geometry>

                <!-- Create a composite shape. -->
                <GeometryGroup>
                  <EllipseGeometry Center="50,50" RadiusX="45" RadiusY="20" />
                  <EllipseGeometry Center="50,50" RadiusX="20" RadiusY="45" />
                </GeometryGroup>
              </GeometryDrawing.Geometry>
              <GeometryDrawing.Brush>

                <!-- Paint the drawing with a gradient. -->
                <LinearGradientBrush>
                  <GradientStop Offset="0.0" Color="Blue" />
                  <GradientStop Offset="1.0" Color="#CCCCFF" />
                </LinearGradientBrush>
              </GeometryDrawing.Brush>
              <GeometryDrawing.Pen>

                <!-- Outline the drawing with a solid color. -->
                <Pen Thickness="10" Brush="Black" />
              </GeometryDrawing.Pen>
            </GeometryDrawing>
          </DrawingImage.Drawing>
        </DrawingImage>
      </Image.Source>
    </Image>
  </Border>


</Page>

Version Information

.NET Framework
Available since 3.0
Silverlight
Available since 2.0
Windows Phone Silverlight
Available since 7.0

Thread Safety

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