Information
The topic you requested is included in another documentation set. For convenience, it's displayed below. Choose Switch to see the topic in its original location.

UIElement.OnRender Method

When overridden in a derived class, participates in rendering operations that are directed by the layout system. The rendering instructions for this element are not used directly when this method is invoked, and are instead preserved for later asynchronous use by layout and drawing.

Namespace:  System.Windows
Assembly:  PresentationCore (in PresentationCore.dll)
protected virtual void OnRender(
	DrawingContext drawingContext
)
You cannot use methods in XAML.

Parameters

drawingContext
Type: System.Windows.Media.DrawingContext

The drawing instructions for a specific element. This context is provided to the layout system.

This method has no default implementation in the UIElement class.

Notes to Inheritors:

The OnRender method can be overridden to add further graphical elements (not previously defined in a logical tree) to a rendered element, such as effects or adorners. A DrawingContext object is passed as an argument, which provides methods for drawing shapes, text, images or videos.

The following code example shows a possible implementation for a panel derived class.

// Override the OnRender call to add a Background and Border to the OffSetPanel 
protected override void OnRender(DrawingContext dc)
{
    SolidColorBrush mySolidColorBrush  = new SolidColorBrush();
    mySolidColorBrush.Color = Colors.LimeGreen;
    Pen myPen = new Pen(Brushes.Blue, 10);
    Rect myRect = new Rect(0, 0, 500, 500);
    dc.DrawRectangle(mySolidColorBrush, myPen, myRect);
}

Windows 7, Windows Vista, Windows XP SP2, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003

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

.NET Framework

Supported in: 3.5, 3.0

Community Additions

Show:
© 2014 Microsoft. All rights reserved.