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LazyInitializer.EnsureInitialized<T> Method (T%, Func<T>)

Initializes a target reference type using the specified function if it has not already been initialized.

Namespace:  System.Threading
Assembly:  mscorlib (in mscorlib.dll)

public static T EnsureInitialized<T>(
	ref T target,
	Func<T> valueFactory
where T : class

Type Parameters


The reference type of the reference to be initialized.


Type: T%
The reference of type T to initialize if it has not already been initialized.
Type: System.Func<T>
The Func<T> invoked to initialize the reference.

Return Value

Type: T
The initialized value of type T.


Type T does not have a default constructor.


valueFactory returned null (Nothing in Visual Basic).

This method may only be used on reference types, and valueFactory may not return a null reference (Nothing in Visual Basic). To ensure initialization of value types or to allow null reference types, see other overloads of EnsureInitialized.

This method may be used concurrently by multiple threads to initialize target.

In the event that multiple threads access this method concurrently, multiple instances of T may be created, but only one will be stored into target. In such an occurrence, this method will not dispose of the objects that were not stored. If such objects must be disposed, it is up to the caller to determine if an object was not used and to then dispose of the object appropriately.

.NET Framework

Supported in: 4

.NET Framework Client Profile

Supported in: 4

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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