Freigeben über


ScaleTransform Class

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Scales an object in the two-dimensional x-y coordinate system.

Inheritance Hierarchy

System.Object
  System.Windows.DependencyObject
    System.Windows.Media.GeneralTransform
      System.Windows.Media.Transform
        System.Windows.Media.ScaleTransform

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

Syntax

'Declaration
Public NotInheritable Class ScaleTransform _
    Inherits Transform
public sealed class ScaleTransform : Transform
<ScaleTransform .../>

The ScaleTransform type exposes the following members.

Constructors

  Name Description
Public methodSupported by Silverlight for Windows Phone ScaleTransform Initializes a new instance of the ScaleTransform class.

Top

Properties

  Name Description
Public propertySupported by Silverlight for Windows Phone CenterX Gets or sets the x-coordinate of the center point of this ScaleTransform.
Public propertySupported by Silverlight for Windows Phone CenterY Gets or sets the y-coordinate of the center point of this ScaleTransform.
Public propertySupported by Silverlight for Windows Phone Dispatcher Gets the Dispatcher this object is associated with. (Inherited from DependencyObject.)
Public propertySupported by Silverlight for Windows Phone Inverse Gets the inverse of this transform, if it exists. (Inherited from Transform.)
Public propertySupported by Silverlight for Windows Phone ScaleX Gets or sets the x-axis scale factor.
Public propertySupported by Silverlight for Windows Phone ScaleY Gets or sets the y-axis scale factor.

Top

Methods

  Name Description
Public methodSupported by Silverlight for Windows Phone CheckAccess Determines whether the calling thread has access to this object. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone ClearValue Clears the local value of a dependency property. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone Equals(Object) Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected methodSupported by Silverlight for Windows Phone Finalize Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone GetAnimationBaseValue Returns any base value established for a Silverlight dependency property, which would apply in cases where an animation is not active. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone GetHashCode Serves as a hash function for a particular type. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone GetType Gets the Type of the current instance. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone GetValue Returns the current effective value of a dependency property from a DependencyObject. (Inherited from DependencyObject.)
Protected methodSupported by Silverlight for Windows Phone MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone ReadLocalValue Returns the local value of a dependency property, if a local value is set. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone SetValue Sets the local value of a dependency property on a DependencyObject. (Inherited from DependencyObject.)
Public methodSupported by Silverlight for Windows Phone ToString Returns a string that represents the current object. (Inherited from Object.)
Public methodSupported by Silverlight for Windows Phone Transform Transforms the specified point and returns the result. (Inherited from GeneralTransform.)
Public methodSupported by Silverlight for Windows Phone TransformBounds Transforms the specified bounding box and returns an axis-aligned bounding box that is exactly large enough to contain it. (Inherited from Transform.)
Public methodSupported by Silverlight for Windows Phone TryTransform Attempts to transform the specified point and returns a value that indicates whether the transformation was successful. (Inherited from Transform.)

Top

Fields

  Name Description
Public fieldStatic memberSupported by Silverlight for Windows Phone CenterXProperty Identifies the CenterX dependency property.
Public fieldStatic memberSupported by Silverlight for Windows Phone CenterYProperty Identifies the CenterY dependency property.
Public fieldStatic memberSupported by Silverlight for Windows Phone ScaleXProperty Identifies the ScaleX dependency property.
Public fieldStatic memberSupported by Silverlight for Windows Phone ScaleYProperty Identifies the ScaleY dependency property.

Top

Remarks

Use a ScaleTransform to stretch or shrink an object horizontally or vertically. The ScaleX property specifies the amount to stretch or shrink an object along the x-axis, and the ScaleY property specifies the amount to stretch or shrink an object along the y-axis. Scale operations are centered on the point specified by the CenterX and CenterY properties.

The local 0,0 for an object can be offset on a Canvas using Canvas.Left and Canvas.Top, but this does not count as a transform; the object retains its own local 0,0 in this case for transform purposes.

Multiple transforms can be applied with a TransformGroup. Custom transforms can be created with a MatrixTransform.

Transforms can alter the display of text in your application to create a decorative effect. The following illustration shows the second line of text scaled by 150% along the x-axis, and the third line of text scaled by 150% along the y-axis.

TextBlock using a ScaleTransform

Transformed text.

NoteNote:

Scaling text is not the same as increasing the font size of text. Font sizes are calculated independently of each other in order to provide the best resolution at different sizes. Scaled text, on the other hand, preserves the proportions of the original-sized text.

Examples

The following XAML example uses a ScaleTransform to scale text from its original size.

Run this sample

<StackPanel>
<TextBlock
  FontFamily="Verdana"
  FontSize="32"
  FontWeight="Bold" 
  Foreground="SteelBlue"
  Text="Scaled Text" />

<!-- Scale the text width using a ScaleTransform. -->
<TextBlock
  FontFamily="Verdana"
  FontSize="32"
  FontWeight="Bold" 
  Foreground="SteelBlue"
  Text="Scaled Text">
  <TextBlock.RenderTransform>
    <ScaleTransform ScaleX="1.5" ScaleY="1.0" />
  </TextBlock.RenderTransform>
</TextBlock>

<!-- Scale the text height using a ScaleTransform. -->
<TextBlock
  FontFamily="Verdana"
  FontSize="32"
  FontWeight="Bold" 
  Foreground="SteelBlue"
  Text="Scaled Text">
  <TextBlock.RenderTransform>
    <ScaleTransform ScaleX="1.0" ScaleY="1.5" />
  </TextBlock.RenderTransform>
</TextBlock>
</StackPanel>

Transform objects can be accessed and manipulated by using code. One way to do this is to name the Transform and then access it by using code. The following example shows how to increase the ScaleX and ScaleY property values of a ScaleTransform applied to a Rectangle every time that Rectangle is clicked.

Run this sample

<StackPanel>
  <Rectangle MouseLeftButtonDown="HandleMouseButtonDown"
    Width="50" Height="50" Fill="RoyalBlue">
    <Rectangle.RenderTransform>

      <!-- If you give the transform a name you can 
        access it easily from code. -->
      <ScaleTransform x:Name="myScaleTransform" />
    </Rectangle.RenderTransform>
  </Rectangle>
</StackPanel>
Private Sub HandleMouseButtonDown(ByVal sender As Object, ByVal e As MouseButtonEventArgs)
    ' Increase ScaleX and ScaleY by 25%.
    myScaleTransform.ScaleX = (myScaleTransform.ScaleX * 1.25)
    myScaleTransform.ScaleY = (myScaleTransform.ScaleY * 1.25)
End Sub
private void HandleMouseButtonDown(object sender, MouseButtonEventArgs e)
{
    // Increase ScaleX and ScaleY by 25%.
    myScaleTransform.ScaleX = myScaleTransform.ScaleX * 1.25;
    myScaleTransform.ScaleY = myScaleTransform.ScaleY * 1.25;
}

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

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.