Windows Data types

The following are the Common window types for MSDN:

1. The interface type of the calling function:

Data type	Describe
Apientry	The application portal, calling the Convention's system functions, is defined in WinDef.h as follows #define Apientry WINAPI
winapi	Application portal, calling convention system functions, defined in WinDef.h as follows #define WINAPI __stdcall
callback	Application portal, calling convention system functions, defined in WinDef.h as follows #define CALLBACK __stdcall
Attention	Apientry/winapi/callback use __stdcall for function calls, but only callback to specify callback functions, the window API calls with WINAPI.

2. Message-related types

WPARAM	typedef uint_ptr WPARAM;
uint_ptr	an unsigned int_ptr
lparam	a message parameter, this type in WinDef.h is defined as follows: typedef LONG _ptr WPARAM;
Long_ptr	A signed pointer-type data, pointing to a long

3. Handle correlation: Handle is a special smart pointer, when an application sequence to refer to other system memory or management objects can use the handle, in short, the front with the beginning of H is usually a handle to the XXX.

HWND	A handle to the window that is defined in WinDef.h: typedef HANDLE HWND
HANDLE	A handle to a pointer to an object. The following are defined in WinNT.h: typedef PVOID HANDLE
PVOID	Pointers to any type are defined in WinNT.h: typedef void *pvoid
Hicon	Handle to Icon

Windows Data types