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Marshal.AreComObjectsAvailableForCleanup Method

Indicates whether runtime callable wrappers (RCWs) from any context are available for cleanup.

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

static member AreComObjectsAvailableForCleanup : unit -> bool 

Return Value

Type: System.Boolean
true if there are any RCWs available for cleanup; otherwise, false.

If there are a lot of references between managed and native code with deep dependency graphs it can take a long time for all the objects to clean up. Each time a GC runs it will free up some number of RCWs, which will in turn release the underlying COM objects. Those COM objects will then release their managed references and make more objects available for cleanup the next time a GC runs, which starts the process over again.

The AreComObjectsAvailableForCleanup method provides a way for the application to determine how many cycles of GC.Collect and GC.WaitForPendingFinalizers need to happen in order to clean everything up.

.NET Framework

Supported in: 4

.NET Framework Client Profile

Supported in: 4

  • SecurityCriticalAttribute 

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

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.