ExportProvider::GetExportedValueOrDefault<T> Method (String^)


The .NET API Reference documentation has a new home. Visit the .NET API Browser on docs.microsoft.com to see the new experience.

Gets the exported object with the specified contract name or the default value for the specified type, or throws an exception if there is more than one matching exported object.

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

generic<typename T>
T GetExportedValueOrDefault(
	String^ contractName


Type: System::String^

The contract name of the exported object to return, or null or an empty string ("") to use the default contract name.

Return Value

Type: T

The exported object with the specified contract name, if found; otherwise, the default value for T.

Type Parameters


The type of the exported object to return.

Exception Condition

There is more than one exported object with the specified contract name in the CompositionContainer.


The CompositionContainer object has been disposed of.


The underlying exported object cannot be cast to T.


An error occurred during composition. Errors will contain a collection of errors that occurred.

If the exported object is not found, this method returns the appropriate default value for T; for example, zero for integer types, false for Boolean types, and null for reference types.

The default contract name is the result of calling the GetContractName method on T.

The contract name is compared by using the Ordinal property to perform a case-sensitive, non-linguistic comparison.

.NET Framework
Available since 4.0
Portable Class Library
Supported in: portable .NET platforms
Available since 4.0
Return to top