GC.KeepAlive Method
Microsoft Silverlight will reach end of support after October 2021. Learn more.
References the specified object, which makes it ineligible for garbage collection from the start of the current routine to the point where this method is called.
Namespace: System
Assembly: mscorlib (in mscorlib.dll)
Syntax
'Declaration
Public Shared Sub KeepAlive ( _
obj As Object _
)
public static void KeepAlive(
Object obj
)
Parameters
- obj
Type: System.Object
The object to reference.
Remarks
The purpose of the KeepAlive method is to ensure the existence of a reference to an object that is at risk of being prematurely reclaimed by the garbage collector. A common scenario where this might happen is when there are no references to the object in managed code or data, but the object is still in use in unmanaged code such as Win32 APIs, unmanaged DLLs, or methods using COM.
This method references the obj parameter, making that object ineligible for garbage collection from the start of the routine to the point, in execution order, where this method is called. Code this method at the end, not the beginning, of the range of instructions where obj must be available.
The KeepAlive method performs no operation and produces no side effects other than extending the lifetime of the object passed in as a parameter.
Version Information
Silverlight
Supported in: 5, 4, 3
Silverlight for Windows Phone
Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0
XNA Framework
Supported in: Xbox 360, Windows Phone OS 7.0
Platforms
For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.