Network programming in C#, Network Programming in VB.NET, Network Programming in .NET
Available now!
Buy at Amazon US or
Buy at Amazon UK


» Windows API reference
» Webcam streaming in VB.NET
» Remoting with firewalls
» RSA from first principles
» Key & MouseLogger in .NET
» Networking Resource Kit for .NET
» Migrating VB6 Winsock to VB.NET
» Migrating C++ sockets to C#
» RFC Reference guide
» COM Reference guide
» WMI Reference guide
» SQL stored procedures
» TCP & UDP port reference
» NET Framework reference
» Ethernet Type codes
» MAC address assignments
» DLL entry point reference
» Boost SQL performance
» Free SMS UK
» Free SMS Ireland
» Free SMS South Africa
» Internet Explorer

Contact us

GetWindowRgn Reference in C#, VB.NET and VB6


Visual Basic 6 definition
Declare Function GetWindowRgn Lib "user32.dll" (ByVal hWnd As Long, ByVal hRgn As Long) As Long

Visual Basic .NET definition
Declare Function GetWindowRgn Lib "user32" (ByVal hwnd As Integer, ByVal hRgn As Integer) As Integer

C# definition
[DllImport("user32")] public static extern int GetWindowRgn(int hwnd, int hRgn)


GetWindowRgn obtains a copy of a window's current region. If a non-empty region is applied to a window, it resticts the area of the window that is visible, effectively changing its shape as far as the user is concerned. This function copies a window's region into a second region passed to the function. GetWindowRgn Gets a copy of the window region of a window. System.Windows.Forms.Control.Region

Return Value

The function returns one of the following flags specifying the result of the region combination operation: ERROR An error occured while trying to combine the regions. NULLREGION The combined region is empty, i.e., null. SIMPLEREGION The combined region forms a rectangle. COMPLEXREGION The combined region is not empty but is also not a rectangle.



Further Information:

For further information on Windows API functions such as these, and how to use these API's in your C# and VB.NET applications, please refer to the book 'Network programming in .NET' (Buy at Amazon UK) (Buy at Amazon US)

Visual Basic 6 example source code

Visual Basic .NET example source code

Provide a code example



Copyright 2017 Infinite Loop Ltd.