Artigo
11/18/2011

ExportFactory<T> Class

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

Creates new instances of a part that provides the specified export.

Inheritance Hierarchy

System.Object
System.ComponentModel.Composition.ExportFactory<T>
System.ComponentModel.Composition.ExportFactory<T, TMetadata>

Namespace: System.ComponentModel.Composition
Assembly: System.ComponentModel.Composition.Initialization (in System.ComponentModel.Composition.Initialization.dll)

Syntax

'Declaration
Public Class ExportFactory(Of T)

public class ExportFactory<T>

Type Parameters

T
The type of the export.

The ExportFactory<T> type exposes the following members.

Constructors

	Name	Description
	ExportFactory<T>	Initializes a new instance of the ExportFactory<T> class.

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Methods

	Name	Description
	CreateExport	Creates an instance of the factory's export.
	Equals(Object)	Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
	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.)
	GetHashCode	Serves as a hash function for a particular type. (Inherited from Object.)
	GetType	Gets the Type of the current instance. (Inherited from Object.)
	MemberwiseClone	Creates a shallow copy of the current Object. (Inherited from Object.)
	ToString	Returns a string that represents the current object. (Inherited from Object.)

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Remarks

When using an indirect reference to a part via a Lazy<T> object, the Value property always returns a reference to the same object. In some circumstances, this is not desirable, and you would like each reference to result in the creation of a new object. ExportFactory<T> is designed for those scenarios.

ExportFactory<T> can be used in a similar fashion to Lazy<T> when creating attributed parts. That is, an import contract defined on ExportFactory<T> with a generic parameter of T will match an export defined on T. For example, the follow export and import match:

[Export]
public String myData = "Example Data.";

[Import]
public ExportFactory<String> theData { get; set; }

<Export()>
Public myData As String = "Example Data."

<Import()>
Public Property theData As ExportFactory(Of String)

The value returned from the CreateExport method is an ExportLifetimeContext<T> object, which has two pieces. The Value property provide access to the created part. Calling the Dispose method of the ExportLifetimeContext<T> object will clean up the created part and all of its dependencies, allowing its lifetime to be managed without reference to the container that created it.

Version Information

Silverlight

Supported in: 5, 4

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.

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