SafeHandle.DangerousAddRef Method (Boolean)


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Manually increments the reference counter on SafeHandle instances.

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

public void DangerousAddRef(
	ref bool success


Type: System.Boolean

true if the reference counter was successfully incremented; otherwise, false.

The DangerousAddRef method prevents the common language runtime from reclaiming memory used by a handle (which occurs when the runtime calls the ReleaseHandle method). You can use this method to manually increment the reference count on a SafeHandle instance. DangerousAddRef returns a Boolean value using a ref parameter (success) that indicates whether the reference count was incremented successfully. This allows your program logic to back out in case of failure. You should set success to false before calling DangerousAddRef. If success is true, avoid resource leaks by matching the call to DangerousAddRef with a corresponding call to DangerousRelease.


This method is intended for advanced users and must always be used carefully. To avoid leaking handle resources, always call this method inside a constrained execution region (CER), where a thread abort cannot interrupt processing.


for permission to call unmanaged code. Security action: LinkDemand. Associated enumeration: SecurityPermissionFlag.UnmanagedCode

Universal Windows Platform
Available since 8
.NET Framework
Available since 2.0
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1
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