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Greetings and a happy new year.
If the code runs below, then I receive a funny result in the 2. MSGBOX.
The 1. MSGBOX shows me the value 20. That is okay. But the 2. MSGBOX shows 10.
Is there inside the WndProc only a limited use of global variables allowed?
Please can somebody explain me this conduct.
Thank you
Norbert
(PBWin 7.04 / Win 98 SE)
If the code runs below, then I receive a funny result in the 2. MSGBOX.
The 1. MSGBOX shows me the value 20. That is okay. But the 2. MSGBOX shows 10.
Is there inside the WndProc only a limited use of global variables allowed?
Please can somebody explain me this conduct.
Thank you
Norbert
(PBWin 7.04 / Win 98 SE)
Code:
#COMPILE EXE
#DIM ALL
#INCLUDE "WIN32API.INC"
GLOBAL hWndMain AS LONG
GLOBAL g_var AS LONG
FUNCTION WINMAIN (BYVAL hInstance AS LONG, _
BYVAL hPrevInstance AS LONG, _
lpCmdLine AS ASCIIZ PTR, _
BYVAL iCmdShow AS LONG) AS LONG
LOCAL Msg AS tagMsg
LOCAL w_ndclass AS WndClassEx
LOCAL szClassName AS ASCIIZ * 80
LOCAL hWnd AS LONG
LOCAL hMenu AS LONG
szClassName = "MYPROGRAM32"
w_ndclass.cbSize = SIZEOF(W_ndClass)
w_ndclass.style = %CS_HREDRAW OR %CS_VREDRAW
w_ndclass.lpfnWndProc = CODEPTR(WndProc)
w_ndclass.cbClsExtra = 0
w_ndclass.cbWndExtra = 0
w_ndclass.hInstance = hInstance
w_ndclass.hIcon = LoadIcon(hInstance, "PROGRAM")
w_ndclass.hCursor = LoadCursor(%NULL, BYVAL %IDC_ARROW)
w_ndclass.hbrBackground = GetStockObject(%WHITE_BRUSH) '%WHITE_BRUSH)
w_ndclass.lpszMenuName = %NULL
w_ndclass.lpszClassName = VARPTR(szClassName)
w_ndclass.hIconSm = LoadIcon(hInstance, BYVAL %IDI_APPLICATION)
RegisterClassEx w_ndclass
hWndMain = CreateWindowEx(0, szClassName, _
"Test", _
%WS_OVERLAPPEDWINDOW, _
100, _
100, _
700, _
400, _
%HWND_DESKTOP, _
hMenu, _
hInstance, _
BYVAL %NULL)
ShowWindow hWndMain, iCmdShow
UpdateWindow hWndMain
WHILE GetMessage(Msg, %NULL, 0, 0)
TranslateMessage Msg
DispatchMessage Msg
WEND
FUNCTION = msg.wParam
END FUNCTION
FUNCTION WndProc (BYVAL hWnd AS LONG, BYVAL wMsg AS LONG, _
BYVAL wParam AS LONG, BYVAL lParam AS LONG) EXPORT AS LONG
g_var = 10
SELECT CASE wMsg
CASE %WM_CREATE
g_var = g_var + 10
MSGBOX STR$(g_var),,"1. MSGBOX"
MSGBOX STR$(g_var),,"2. MSGBOX"
PostQuitMessage 0
FUNCTION = 0
EXIT FUNCTION
END SELECT
FUNCTION = DefWindowProc(hWnd, wMsg, wParam, lParam)
END FUNCTION
)
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