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RegisterClassEx Reference in C#, VB.NET and VB6


Visual Basic 6 definition
Declare Function RegisterClassEx Lib "user32.dll" Alias "RegisterClassExA" (lpwcx As WNDCLASSEX) As Long

Visual Basic .NET definition
Declare Function RegisterClassEx Lib "user32" Alias "RegisterClassExA" (ByRef pcWndClassEx As WNDCLASSEX) As Short

C# definition
[DllImport("user32", EntryPoint="RegisterClassEx")] public static extern short RegisterClassExA(ref WNDCLASSEX pcWndClassEx)


RegisterClassEx registers a new window class for use. Only after registering the window class can it be used to create windows. After the window class is completely finished being used, use UnregisterClass to unregister it.

Return Value

If an error occured, the function returns 0. If successful, the function returns an atom identifying the class.


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

C# example source code

Provide a code example



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