#include <windows.h>

#include "resource.h"

LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM) ;

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow) {

    DialogBox( hInstance, ( LPCTSTR ) IDD_DIALOG1, NULL, ( DLGPROC ) WndProc );
    return 0;
}

LRESULT CALLBACK WndProc(HWND hDlg, UINT uMsg, WPARAM wParam, LPARAM lParam) {

    switch(uMsg){

      case WM_INITDIALOG:

        {

        }

        break;

      case WM_COMMAND:

        switch(LOWORD( wParam )) {

          case IDOK:

            {

                EndDialog( hDlg, 0 );

            }

            break;

        };

        break;

      case WM_CLOSE:

        EndDialog( hDlg, 0 );

        break;

    };

    return 0;
}

看到 DialogBox 函数的例子 怎么最后个函数总是如上例一样使用 CALLBACK 进行修饰？但是其原型是
INT_PTR DialogBox(          HINSTANCE hInstance,
    LPCTSTR lpTemplate,
    HWND hWndParent,
    DLGPROC lpDialogFunc
);
好像并不是需要CALLBACK函数，到底怎么回事呢？

CALLBACK WndProc（）？

LRESULT CALLBACK 是函数类型修饰？有什么问题吗