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

.NET Framework (current version)

Initializes a target reference type by using a specified function if it hasn't 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: T

The reference of type T to initialize if it hasn't already been initialized.

Type: System.Func<T>

The function that is called to initialize the reference.

Return Value

Type: T

The initialized value of type T.

Type Parameters


The reference type of the reference to be initialized.

Exception Condition

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.

Universal Windows Platform
Available since 8
.NET Framework
Available since 4.0
Portable Class Library
Supported in: portable .NET platforms
Windows Phone Silverlight
Available since 8.0
Windows Phone
Available since 8.1
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