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Lazy<T>.IsValueCreated Property

Gets a value that indicates whether a value has been created for this Lazy<T> instance.

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

public bool IsValueCreated { get; }

Property Value

Type: System.Boolean
true if a value has been created for this Lazy<T> instance; otherwise, false.

When lazy initialization occurs for a Lazy<T> instance, it may result in either a value being created or an exception being thrown. If an exception is thrown, subsequent behavior of the Lazy<T> instance depends on whether exception caching is in effect. If the Lazy<T> instance was created by using a constructor that does not specify an initialization function, then exception caching is not in effect. A subsequent attempt to initialize the Lazy<T> might succeed, and after successful initialization the IsValueCreated property returns true. If the Lazy<T> instance was created with an initialization function (specified by the valueFactory parameter of the Lazy<T> constructor), then exception caching is controlled by the thread safety mode.

  • If the mode is LazyThreadSafetyMode.ExecutionAndPublication or LazyThreadSafetyMode.None, there is no second chance to initialize the Lazy<T> instance. If an exception occurs and is unhandled in the initialization function, that exception is cached and rethrown on subsequent accesses of the Lazy<T>.Value property. No value is created if an exception is thrown, so in such cases IsValueCreated returns false.

  • If the mode is LazyThreadSafetyMode.PublicationOnly, the first thread that succeeds in running the initialization function (or the default constructor) creates the value for the Lazy<T> instance. If the initialization function throws an exception on one thread, other threads can still try to initialize the Lazy<T> instance. Until the value is created, the IsValueCreated property returns false.

.NET Framework

Supported in: 4.5.2, 4.5.1, 4.5, 4

.NET Framework Client Profile

Supported in: 4

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone 8, Silverlight 8.1

Windows Phone 8.1, Windows Phone 8, 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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