LabVIEW 消息处理函数 dll callback

lichenglongllx

    我在LabVIEW中通过dll调用，捕获了wm_paint消息！但程序却变得异常！请各位指教！现将dll代码贴上！


#include "windows.h"
static WNDPROC prevProc;
static xx=1;
  
_declspec(dllexport) LRESULT CALLBACK WinSunProc(HWND hWnd,UINT uMsg,WPARAM wParam, LPARAM lParam )  //
{
HDC hdc;
PAINTSTRUCT ps;
   f(uMsg==WM_PAINT)
    {
  hdc=::BeginPaint(hWnd,&ps);
  :ineTo(hdc,50*xx,50*xx);
     xx++;
  ::EndPaint(hWnd,&ps);
  xx=+5;
        return 1;
    }
    else {
return prevProc(hWnd,uMsg,wParam,lParam);
    }
}
_declspec(dllexport) int SetWinLong(HWND hWnd)
{  
  prevProc=(WNDPROC)::GetWindowLong(hWnd,GWL_WNDPROC);
  SetWindowLong(hWnd,GWL_WNDPROC,(LONG)WinSunProc);
  return(1);
}