🚀 go-pugleaf

In article <1993Jan9.085030.11967%gtonwu@Uz.nthu.edu.tw> gtonwu@Uz.nthu.edu.tw (Tony) writes:
>Hi, there 
>
>     I am confused by type data types of MSC ! I don't know what is the
>     difference among them , since I was simply using int,unsigned,char..
>     while I did programming under MS-DOS before    !
>
>     Would someone kind enough to tell me the distict difference of the 
>     following !?
>
>       WORD , DWORD, LONG, WPARAM, LPARAM , ... 
>
>       and some others I have to know !

	They are all defined in windows.h.  Look in there and you
	will see those and many others.  But you really don't
	have to know what they are because you will *not* be
	manipulating or touching them yourself.  MS provides
	all you need.

	For example, when you get a WM_PAINT message, you need
	an HDC (handle to a device context) to call any of
	the GDI drawing functions.  What is it?  Who cares!
	But you do need one.  So, just declare it and use
	it as the function tells you:
		HDC hdc;
		PAINTSTRUCT ps;
		...
		  case WM_PAINT:  hdc=BeginPaint(hdc,&ps);
				  ...gdi functions(hdc,....);
				  EndPaint(hwnd,&ps);
				  break;
	Also, if a windows message tells you that LPARAM contains
	a POINT structure, then just retrieve it with:
		POINT pt;
		pt=MAKEPOINT(lparam);

	Usually, the help for each function describes the functions
	and their parameters, returned values etc.

	Ok, so I lied.  You do need to know a few things, like
	what is a POINT structure.  You can look up all of these
	things in windows.h and in the docs.

	The definitions of HWND,HDC, etc depend on whether you
	use #define STRICT or not (see windows.h).  I strongly
	recommend that you use:
		#define STRICT
		#include <windows.h>
	Most of the HDC, HWND, etc are all just UINT or WORD,
	i.e. just 'int' values when you get right down to it,
	so it is not possible for the compiler to check whether
		function1(hdc,hwnd);
	    or	function2(hwnd,hdc);
	is correct.  If you use STRICT, then they are defined
	as pointers to unique structs and the compiler can
	tell you if you are wrong.  I also highly recommend
	enabling every single warning message that your
	compiler can possibly report.  Make sure it warns
	about everything and act on every warning until
	it is quiet.  Your app will be significantly more
	reliable.

-- 
John A. Grant						jagrant@emr1.emr.ca
Airborne Geophysics
Geological Survey of Canada, Ottawa