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Marshal.GetLastWin32Error Method

Returns the error code returned by the last unmanaged function called using platform invoke that has the DllImportAttribute.SetLastError flag set.

[Visual Basic]
Public Shared Function GetLastWin32Error() As Integer
public static int GetLastWin32Error();
public: static int GetLastWin32Error();
public static function GetLastWin32Error() : int;

Return Value

The last error code set by a call to the Win32 SetLastError API method.


GetLastWin32Error exposes the Win32 GetLastError API method from Kernel32.DLL. This method exists because it is not safe to make a direct platform invoke call to GetLastError to obtain this information. If you want to access this error code, you must call GetLastWin32Error rather than writing your own platform invoke definition for GetLastError and calling it. The common language runtime can make internal calls to APIs that overwrite the operating system maintained GetLastError.

You can only use this method to obtain error codes if you apply the System.Runtime.InteropServices.DllImportAttribute to the method signature and set the SetLastError field to true. The process for this varies depending upon the source language used: C# and C++ are false by default, but the Declare statement in Visual Basic is true. For additional information about the GetLastError and SetLastError Win32 API methods, see the MSDN Library.

Note   This method uses SecurityAction.LinkDemand to prevent it from being called from untrusted code; only the immediate caller is required to have SecurityPermissionAttribute.UnmanagedCode permission. If your code can be called from partially trusted code, do not pass user input to Marshal class methods without validation. For important limitations on using the LinkDemand member, see Demand vs. LinkDemand.


Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family, .NET Compact Framework

.NET Framework Security: 

See Also

Marshal Class | Marshal Members | System.Runtime.InteropServices Namespace | DllImportAttribute