RuntimeHelpers Class
Assembly: mscorlib (in mscorlib.dll)
The following code example shows how to reliably set handles using the PrepareConstrainedRegions method. To reliably set a handle to a specified pre-existing handle, you need to ensure that the allocation of the native handle and the subsequent recording of that handle within a SafeHandle object is atomic. Any failure between these operations (such as a thread abort or out of memory exception) will result in the native handle being leaked. You can use the PrepareConstrainedRegions method to make sure that the handle is not leaked.
[StructLayout(LayoutKind.Sequential)] struct MyStruct { public IntPtr m_outputHandle; } sealed class MySafeHandle : SafeHandle { // Called by P/Invoke when returning SafeHandles public MySafeHandle() : base(IntPtr.Zero, true) { } public MySafeHandle AllocateHandle() { // Allocate SafeHandle first to avoid failure later. MySafeHandle sh = new MySafeHandle(); RuntimeHelpers.PrepareConstrainedRegions(); try { } finally { MyStruct myStruct = new MyStruct(); NativeAllocateHandle(ref myStruct); sh.SetHandle(myStruct.m_outputHandle); } return sh; }
Windows 98, Windows Server 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
The Microsoft .NET Framework 3.0 is supported on Windows Vista, Microsoft Windows XP SP2, and Windows Server 2003 SP1.