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Freezable.Clone Method

Creates a modifiable clone of the Freezable, making deep copies of the object's values. When copying the object's dependency properties, this method copies expressions (which might no longer resolve) but not animations or their current values.

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

public Freezable Clone()

Return Value

Type: System.Windows.Freezable
A modifiable clone of the current object. The cloned object's IsFrozen property is false even if the source's IsFrozen property is true.

The Clone and CloneCurrentValue methods produce modifiable clones of frozen Freezable objects (the methods also clone Freezable objects that are not frozen). The clone is effectively a deep copy of the current object.

The following table summarizes the differences between the Clone and CloneCurrentValue methods.

Action

Clone method behavior

CloneCurrentValue method behavior

Copying a dependency property that has an expression

The expression is copied, but might no longer resolve. For more information, see Freezable Objects Overview.

The current value of the expression is copied, but not the expression itself.

Copying an animated dependency property

The property's base (non-animated) value is copied. Animations are not copied.

The property's current animated value is copied. Animations are not copied.

Note that unset properties are not copied. If an unset property has a default value that is a frozen Freezable, that property value remains frozen in the otherwise modifiable clone.

Move a Freezable Between Threads

This method can be useful for moving a Freezable between threads. First, make the Freezable unmodifiable by calling its Freeze method. Now another thread can access the Freezable and make a local Clone that it can access.

Notes to Inheritors

This method uses CloneCore to produce the clone. To modify the behavior of this method in a derived class, override the CloneCore method.

This example shows how to use the Clone method to create a writable copy of a read-only Freezable.

After a Freezable object is marked as read-only ("frozen"), you cannot modify it. However, you can use the Clone method to create a modifiable clone of the frozen object.

The following example creates a modifiable clone of a frozen SolidColorBrush object.

Button myButton = new Button();
SolidColorBrush myBrush = new SolidColorBrush(Colors.Yellow);

// Freezing a Freezable before it provides 
// performance improvements if you don't 
// intend on modifying it.  
if (myBrush.CanFreeze)
{
    // Makes the brush unmodifiable.
    myBrush.Freeze();
}


myButton.Background = myBrush;  

// If you need to modify a frozen brush, 
// the Clone method can be used to 
// create a modifiable copy.
SolidColorBrush myBrushClone = myBrush.Clone();

// Changing myBrushClone does not change 
// the color of myButton, because its 
// background is still set by myBrush.
myBrushClone.Color = Colors.Red;

// Replacing myBrush with myBrushClone 
// makes the button change to red.
myButton.Background = myBrushClone;

For more information about Freezable objects, see the Freezable Objects Overview.

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

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

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