为custom dialog box class定义两个窗口过程

#include <windows.h>
#include "resource.h"

LRESULT CALLBACK WindowProc(          HWND hwnd,
							UINT uMsg,
							WPARAM wParam,
							LPARAM lParam
							)
{
	switch ( uMsg )
	{
	case WM_CLOSE:
		::PostQuitMessage(0);
		break;
	}

	return ::DefDlgProc(hwnd, uMsg, wParam, lParam);//注意这里不是DefWindowProc
}

BOOL CALLBACK DialogProc(
						 HWND hwndDlg, 
						 UINT uMsg, 
						 WPARAM wParam, 
						 LPARAM lParam
						 )
{
	switch ( uMsg )
	{
	case WM_COMMAND:
		if ( LOWORD(wParam) == IDOK )
			EndDialog(hwndDlg, 1);
		break;
	}
	return FALSE;
}

int WinMain(          HINSTANCE hInstance,
			HINSTANCE hPrevInstance,
			LPSTR lpCmdLine,
			int nCmdShow
			)
{
	WNDCLASSEX wc;
	wc.cbSize = sizeof(wc);
	wc.style = CS_VREDRAW | CS_HREDRAW;//可为赋值为0，但不能不赋值！
	wc.lpfnWndProc = WindowProc;
	wc.cbClsExtra = 0;
	wc.cbWndExtra = DLGWINDOWEXTRA;
	wc.hInstance = hInstance;
	wc.hIcon = ::LoadIcon(NULL, IDI_APPLICATION);
	wc.hCursor = ::LoadCursor(NULL, IDC_ARROW);
	wc.hbrBackground = ::CreateSolidBrush(RGB(255,255,255));
	wc.lpszMenuName = NULL;
	wc.lpszClassName = "mydlgclass";
	wc.hIconSm = NULL;
	::RegisterClassEx(&wc);
	//消息会依经过WindowProc与DialogProc
	DialogBox(hInstance, MAKEINTRESOURCE(IDD_DIALOG1), NULL, DialogProc);
}

rc文件：

IDD_DIALOG1 DIALOGEX 0, 0, 316, 186
STYLE DS_SETFONT | DS_MODALFRAME | DS_FIXEDSYS | DS_CENTER | WS_POPUP | WS_CAPTION | WS_SYSMENU
CAPTION "Dialog"
CLASS "mydlgclass"
FONT 8, "MS Shell Dlg", 400, 0, 0x1
BEGIN
    DEFPUSHBUTTON   "OK",IDOK,205,165,50,14
    PUSHBUTTON      "Cancel",IDCANCEL,259,165,50,14
END