Marshal::Release Method

Decrements the reference count on the specified interface.

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

public:
static int Release(
	IntPtr pUnk
)

Parameters

pUnk
Type: System::IntPtr

The interface to release.

Return Value

Type: System::Int32
The new value of the reference count on the interface specified by the pUnk parameter.

The common language runtime manages the reference count of a COM object for you, making it unnecessary to use this method directly. Use this value only for testing purposes. In rare cases, such as testing a custom marshaler, you might find it necessary to manipulate an object's lifetime manually. Only programs that call Marshal::AddRef should call Release. Calling Release after the reference count has reached zero causes undefined behavior.

You can call Marshal::GetComInterfaceForObject, Marshal::GetIUnknownForObject, or Marshal::GetIDispatchForObject to obtain an IntPtr value that represents a IUnknown interface pointer to release. You can also use these methods and the Release method on managed objects to release the COM interfaces represented by the managed object's COM Callable Wrapper.

The following example demonstrates how to retrieve an IUnknown interface for a managed object using the GetIUnknownForObject method. The example then releases the interface pointer by calling the Release method.

No code example is currently available or this language may not be supported.

.NET Framework

Supported in: 4.5, 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

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 Silverlight 8.1, Windows Phone Silverlight 8

  • SecurityCriticalAttribute 

    requires full trust for the immediate caller. This member cannot be used by partially trusted or transparent code.

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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