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EllipseGeometry Class

Represents the geometry of a circle or ellipse.

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

Namespace:  System.Windows.Media
Assembly:  PresentationCore (in PresentationCore.dll)
XMLNS for XAML: http://schemas.microsoft.com/winfx/2006/xaml/presentation, http://schemas.microsoft.com/netfx/2007/xaml/presentation
public sealed class EllipseGeometry : Geometry
<EllipseGeometry .../>

The EllipseGeometry type exposes the following members.

  Name Description
Public method EllipseGeometry() Initializes a new instance of the EllipseGeometry class.
Public method 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.
Public method 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.
Public method EllipseGeometry(Point, Double, Double, Transform) Initializes a new instance of the EllipseGeometry class that has the specified position, size, and transformation.
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  Name Description
Public property 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.)
Public property CanFreeze Gets a value that indicates whether the object can be made unmodifiable. (Inherited from Freezable.)
Public property Center Gets or sets the center point of the EllipseGeometry.
Public property DependencyObjectType Gets the DependencyObjectType that wraps the CLR type of this instance.  (Inherited from DependencyObject.)
Public property Dispatcher Gets the Dispatcher this DispatcherObject is associated with. (Inherited from DispatcherObject.)
Public property 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.)
Public property IsFrozen Gets a value that indicates whether the object is currently modifiable. (Inherited from Freezable.)
Public property IsSealed Gets a value that indicates whether this instance is currently sealed (read-only). (Inherited from DependencyObject.)
Public property RadiusX Gets or sets the x-radius value of the EllipseGeometry.
Public property RadiusY Gets or sets the y-radius value of the EllipseGeometry.
Public property Transform Gets or sets the Transform object applied to a Geometry. (Inherited from Geometry.)
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  Name Description
Public method 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.)
Public method 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.)
Public method 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.)
Public method 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.)
Public method CheckAccess Determines whether the calling thread has access to this DispatcherObject. (Inherited from DispatcherObject.)
Public method ClearValue(DependencyProperty) Clears the local value of a property. The property to be cleared is specified by a DependencyProperty identifier. (Inherited from DependencyObject.)
Public method ClearValue(DependencyPropertyKey) Clears the local value of a read-only property. The property to be cleared is specified by a DependencyPropertyKey. (Inherited from DependencyObject.)
Public method 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.
Protected method CloneCore Makes the instance a clone (deep copy) of the specified Freezable using base (non-animated) property values. (Inherited from Freezable.)
Public method 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.
Protected method CloneCurrentValueCore Makes the instance a modifiable clone (deep copy) of the specified Freezable using current property values. (Inherited from Freezable.)
Public method CoerceValue 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.)
Protected method CreateInstance Initializes a new instance of the Freezable class. (Inherited from Freezable.)
Protected method CreateInstanceCore When implemented in a derived class, creates a new instance of the Freezable derived class. (Inherited from Freezable.)
Public method Equals Determines whether a provided DependencyObject is equivalent to the current DependencyObject. (Inherited from DependencyObject.)
Public method FillContains(Geometry) Indicates whether the current geometry completely contains the specified Geometry. (Inherited from Geometry.)
Public method FillContains(Point) Indicates whether the geometry contains the specified Point. (Inherited from Geometry.)
Public method FillContains(Geometry, Double, ToleranceType) Indicates whether the current geometry contains the specified Geometry, given the specified margin of error. (Inherited from Geometry.)
Public method FillContains(Point, Double, ToleranceType) Indicates whether the geometry contains the specified Point, given the specified margin of error. (Inherited from Geometry.)
Public method FillContainsWithDetail(Geometry) Returns a value that describes the intersection between the current geometry and the specified geometry. (Inherited from Geometry.)
Public method 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.)
Protected method Finalize Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.)
Public method Freeze() Makes the current object unmodifiable and sets its IsFrozen property to true. (Inherited from Freezable.)
Protected method FreezeCore Makes this Animatable object unmodifiable or determines whether it can be made unmodifiable. (Inherited from Animatable.)
Public method GetAnimationBaseValue Returns the non-animated value of the specified DependencyProperty. (Inherited from Animatable.)
Public method GetArea() Gets the area of the filled region of the Geometry object. (Inherited from Geometry.)
Public method GetArea(Double, ToleranceType) Gets the area of this EllipseGeometry. (Overrides Geometry.GetArea(Double, ToleranceType).)
Public method 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.)
Protected method GetAsFrozenCore Makes the instance a frozen clone of the specified Freezable using base (non-animated) property values. (Inherited from Freezable.)
Public method 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.)
Protected method GetCurrentValueAsFrozenCore Makes the current instance a frozen clone of the specified Freezable. If the object has animated dependency properties, their current animated values are copied. (Inherited from Freezable.)
Public method GetFlattenedPathGeometry() Gets a PathGeometry that is a polygonal approximation of the Geometry object. (Inherited from Geometry.)
Public method GetFlattenedPathGeometry(Double, ToleranceType) Gets a PathGeometry, within the specified tolerance, that is a polygonal approximation of the Geometry object. (Inherited from Geometry.)
Public method GetHashCode Gets a hash code for this DependencyObject. (Inherited from DependencyObject.)
Public method GetLocalValueEnumerator Creates a specialized enumerator for determining which dependency properties have locally set values on this DependencyObject. (Inherited from DependencyObject.)
Public method GetOutlinedPathGeometry() Gets a PathGeometry that is a simplified outline of the filled region of the Geometry. (Inherited from Geometry.)
Public method 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.)
Public method 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.)
Public method 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.)
Public method GetType Gets the Type of the current instance. (Inherited from Object.)
Public method GetValue Returns the current effective value of a dependency property on this instance of a DependencyObject. (Inherited from DependencyObject.)
Public method GetWidenedPathGeometry(Pen) Gets a PathGeometry that is the shape defined by the stroke on the Geometry produced by the specified Pen. (Inherited from Geometry.)
Public method 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.)
Public method InvalidateProperty Re-evaluates the effective value for the specified dependency property (Inherited from DependencyObject.)
Public method IsEmpty Determines whether this EllipseGeometry object is empty. (Overrides Geometry.IsEmpty().)
Public method MayHaveCurves Determines whether this EllipseGeometry object can have curved segments. (Overrides Geometry.MayHaveCurves().)
Protected method MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Protected method OnChanged Called when the current Freezable object is modified. (Inherited from Freezable.)
Protected method OnFreezablePropertyChanged(DependencyObject, DependencyObject) Ensures that appropriate context pointers are established for a DependencyObjectType data member that has just been set. (Inherited from Freezable.)
Protected method OnFreezablePropertyChanged(DependencyObject, DependencyObject, DependencyProperty) This member supports the Windows Presentation Foundation (WPF) infrastructure and is not intended to be used directly from your code. (Inherited from Freezable.)
Protected method OnPropertyChanged Overrides the DependencyObject implementation of OnPropertyChanged to also invoke any Changed handlers in response to a changing dependency property of type Freezable. (Inherited from Freezable.)
Public method ReadLocalValue Returns the local value of a dependency property, if it exists. (Inherited from DependencyObject.)
Protected method ReadPreamble Ensures that the Freezable is being accessed from a valid thread. Inheritors of Freezable must call this method at the beginning of any API that reads data members that are not dependency properties. (Inherited from Freezable.)
Public method SetCurrentValue Sets the value of a dependency property without changing its value source. (Inherited from DependencyObject.)
Public method SetValue(DependencyProperty, Object) Sets the local value of a dependency property, specified by its dependency property identifier. (Inherited from DependencyObject.)
Public method 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.)
Protected method ShouldSerializeProperty Returns a value that indicates whether serialization processes should serialize the value for the provided dependency property. (Inherited from DependencyObject.)
Public method ShouldSerializeTransform Gets a value that indicates whether the value of the Transform property should be serialized. (Inherited from Geometry.)
Public method 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.)
Public method 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.)
Public method 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.)
Public method 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.)
Public method ToString() Creates a string representation of the object based on the current culture. (Inherited from Geometry.)
Public method ToString(IFormatProvider) Creates a string representation of the object using the specified culture-specific formatting information. (Inherited from Geometry.)
Public method VerifyAccess Enforces that the calling thread has access to this DispatcherObject. (Inherited from DispatcherObject.)
Protected method WritePostscript Raises the Changed event for the Freezable and invokes its OnChanged method. Classes that derive from Freezable should call this method at the end of any API that modifies class members that are not stored as dependency properties. (Inherited from Freezable.)
Protected method WritePreamble Verifies that the Freezable is not frozen and that it is being accessed from a valid threading context. Freezable inheritors should call this method at the beginning of any API that writes to data members that are not dependency properties. (Inherited from Freezable.)
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  Name Description
Public event Changed Occurs when the Freezable or an object it contains is modified. (Inherited from Freezable.)
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  Name Description
Public field Static member CenterProperty Identifies the Center dependency property.
Public field Static member RadiusXProperty Identifies the RadiusX dependency property.
Public field Static member RadiusYProperty Identifies the RadiusY dependency property.
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  Name Description
Explicit interface implemetation Private method IFormattable.ToString Formats the value of the current instance using the specified format. (Inherited from Geometry.)
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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.

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

Two EllipseGeometry objects

A GeometryDrawing of two ellipses

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;
        }

    }
}



<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>


More Code

How to: Create a Shape by Using a PathGeometry This example shows how to create a shape using the PathGeometry class. PathGeometry objects are composed of one or more PathFigure objects; each PathFigure represents a different "figure" or shape. Each PathFigure is itself composed of one or more PathSegment objects, each representing a connected portion of the figure or shape. Segment types include LineSegment, ArcSegment, and BezierSegment.
How to: Animate an EllipseGeometry This example shows how to animate a Geometry within a Path element. In the following example, a PointAnimation is used to animate the Center of an EllipseGeometry.
How to: Animate a Point by Using Key Frames This example shows how to use the PointAnimationUsingKeyFrames class to animate a Point.
How to: Create a Composite Shape This example shows how to create composite shapes using Geometry objects and display them using a Path element. In the following example, a LineGeometry, EllipseGeometry, and a RectangleGeometry are used with a GeometryGroup to create a composite shape. The geometries are then drawn using a Path element.

.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.
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