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LinearGradientBrush Class

Paints an area with a linear gradient. This class cannot be inherited.

Namespace: System.Windows.Media
Assembly: PresentationCore (in presentationcore.dll)
XML Namespace:  http://schemas.microsoft.com/winfx/2006/xaml/presentation

public sealed class LinearGradientBrush : GradientBrush
public final class LinearGradientBrush extends GradientBrush
public final class LinearGradientBrush extends GradientBrush
<LinearGradientBrush>
  GradientStops
</LinearGradientBrush>

A LinearGradientBrush paints an area with a linear gradient. A linear gradient defines a gradient along a line. The line's end points are defined by the StartPoint and EndPoint properties of the linear gradient. A LinearGradientBrush brush paints its GradientStops along this line.

The default linear gradient is diagonal. In the default, the StartPoint of a linear gradient is (0,0), the upper-left corner of the area being painted, and its EndPoint is (1,1), the lower-right corner of the area being painted. The colors in the resulting gradient are interpolated along the diagonal path.

The following illustration shows a diagonal gradient. A line was added to highlight the interpolation path of the gradient from the start point to the end point.

A diagonal linear gradient


Gradient axis for a diagonal linear gradient

The next illustration shows the same linear gradient, but with highlighted gradient stops.

A diagonal linear gradient with highlighted gradient stops


Gradient stops in a linear gradient

It's possible to specify a gradient axis that does not completely fill area being painted. When this occurs, the SpreadMethod property is used to determine how the remaining area is painted.

Freezable Features

A LinearGradientBrush 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 the Freezable Objects Overview.

This example shows how to use the LinearGradientBrush class to paint an area with a linear gradient. In the following example, the Fill of a Rectangle is painted with a diagonal linear gradient that transitions from yellow to red to blue to lime green.

<!-- This rectangle is painted with a diagonal linear gradient. -->
<Rectangle Width="200" Height="100">
  <Rectangle.Fill>
    <LinearGradientBrush StartPoint="0,0" EndPoint="1,1">
      <GradientStop Color="Yellow" Offset="0.0" />
      <GradientStop Color="Red" Offset="0.25" />
      <GradientStop Color="Blue" Offset="0.75" />
      <GradientStop Color="LimeGreen" Offset="1.0" />
    </LinearGradientBrush>
  </Rectangle.Fill>
</Rectangle>

Rectangle diagonalFillRectangle = new Rectangle();
diagonalFillRectangle.Width = 200;
diagonalFillRectangle.Height = 100;

// Create a diagonal linear gradient with four stops.   
LinearGradientBrush myLinearGradientBrush =
    new LinearGradientBrush();
myLinearGradientBrush.StartPoint = new Point(0,0);
myLinearGradientBrush.EndPoint = new Point(1,1);
myLinearGradientBrush.GradientStops.Add(
    new GradientStop(Colors.Yellow, 0.0));
myLinearGradientBrush.GradientStops.Add(
    new GradientStop(Colors.Red, 0.25));                
myLinearGradientBrush.GradientStops.Add(
    new GradientStop(Colors.Blue, 0.75));        
myLinearGradientBrush.GradientStops.Add(
    new GradientStop(Colors.LimeGreen, 1.0));
    
// Use the brush to paint the rectangle.
diagonalFillRectangle.Fill = myLinearGradientBrush;

The following illustration shows the gradient created by the previous example.

A diagonal linear gradient

To create a horizontal linear gradient, change the StartPoint and EndPoint of the LinearGradientBrush to (0,0.5) and (1,0.5). In the following example, a Rectangle is painted with a horizontal linear gradient.

<!-- This rectangle is painted with a horizontal linear gradient. -->
<Rectangle Width="200" Height="100">
  <Rectangle.Fill>
    <LinearGradientBrush StartPoint="0,0.5" EndPoint="1,0.5">
      <GradientStop Color="Yellow" Offset="0.0" />
      <GradientStop Color="Red" Offset="0.25" />
      <GradientStop Color="Blue" Offset="0.75" />
      <GradientStop Color="LimeGreen" Offset="1.0" />
    </LinearGradientBrush>
  </Rectangle.Fill>
</Rectangle>

Rectangle horizontalFillRectangle = new Rectangle();
horizontalFillRectangle.Width = 200;
horizontalFillRectangle.Height = 100;

// Create a horizontal linear gradient with four stops.   
LinearGradientBrush myHorizontalGradient =
    new LinearGradientBrush();
myHorizontalGradient.StartPoint = new Point(0,0.5);
myHorizontalGradient.EndPoint = new Point(1,0.5);
myHorizontalGradient.GradientStops.Add(
    new GradientStop(Colors.Yellow, 0.0));
myHorizontalGradient.GradientStops.Add(
    new GradientStop(Colors.Red, 0.25));                
myHorizontalGradient.GradientStops.Add(
    new GradientStop(Colors.Blue, 0.75));        
myHorizontalGradient.GradientStops.Add(
    new GradientStop(Colors.LimeGreen, 1.0));
    
// Use the brush to paint the rectangle.
horizontalFillRectangle.Fill = myHorizontalGradient; 


The following illustration shows the gradient created by the previous example.

A horizontal linear gradient

To create a vertical linear gradient, change the StartPoint and EndPoint of the LinearGradientBrush to (0.5,0) and (0.5,1). In the following example, a Rectangle is painted with a vertical linear gradient.

<!-- This rectangle is painted with a vertical gradient. -->
<Rectangle Width="200" Height="100">
  <Rectangle.Fill>
    <LinearGradientBrush StartPoint="0.5,0" EndPoint="0.5,1">
      <GradientStop Color="Yellow" Offset="0.0" />
      <GradientStop Color="Red" Offset="0.25" />
      <GradientStop Color="Blue" Offset="0.75" />
      <GradientStop Color="LimeGreen" Offset="1.0" />
    </LinearGradientBrush>
  </Rectangle.Fill>
</Rectangle>

Rectangle verticalFillRectangle = new Rectangle();
verticalFillRectangle.Width = 200;
verticalFillRectangle.Height = 100;

// Create a vertical linear gradient with four stops.   
LinearGradientBrush myVerticalGradient =
    new LinearGradientBrush();
myVerticalGradient.StartPoint = new Point(0.5,0);
myVerticalGradient.EndPoint = new Point(0.5,1);
myVerticalGradient.GradientStops.Add(
    new GradientStop(Colors.Yellow, 0.0));
myVerticalGradient.GradientStops.Add(
    new GradientStop(Colors.Red, 0.25));                
myVerticalGradient.GradientStops.Add(
    new GradientStop(Colors.Blue, 0.75));        
myVerticalGradient.GradientStops.Add(
    new GradientStop(Colors.LimeGreen, 1.0));
    
// Use the brush to paint the rectangle.
verticalFillRectangle.Fill = myVerticalGradient;  

The following illustration shows the gradient created by the previous example.

A vertical linear gradient

For additional examples, see the Brushes Sample. For more information about gradients and other types of brushes, see Painting with WPF Brushes.

System.Object
   System.Windows.Threading.DispatcherObject
     System.Windows.DependencyObject
       System.Windows.Freezable
         System.Windows.Media.Animation.Animatable
           System.Windows.Media.Brush
             System.Windows.Media.GradientBrush
              System.Windows.Media.LinearGradientBrush
Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.

.NET Framework

Supported in: 3.0
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