This method creates an exception object for the specified failure HRESULT. If the HRESULT is 0 or positive (a success code), the method returns without creating or throwing an exception.

Note that the Marshal.ThrowExceptionForHR(int) method returns an exception based on the IErrorInfo of the current thread if one is set. When this happens, the errorCode parameter is ignored.

Some failure HRESULTs map to defined exceptions, whereas others do not. If the HRESULT maps to a defined exception, Marshal.ThrowExceptionForHR(int) creates an instance of the exception and throws it. Otherwise, it creates an instance of System.Runtime.InteropServices.COMException, initializes the error code field with the HRESULT, and throws that exception. When Marshal.ThrowExceptionForHR(int) is invoked, it attempts to retrieve extra information regarding the error by using the unmanaged GetErrorInfo function.

For the mapping from each HRESULT to its comparable exception class in the .NET Framework, see How to: Map HRESULTs and Exceptions.

Occasionally, Marshal.ThrowExceptionForHR(int) might return an exception from a previous COM call. In this case, you can use the following workaround and pass IntPtr(-1) as the second parameter (errorInfo):

[SecurityPermissionAttribute(SecurityAction.LinkDemand, Flags = SecurityPermissionFlag.UnmanagedCode)]
public static void ThrowExceptionForHR(int errorCode,IntPtr errorInfo)