【整理】鼠标位置编码（Mouse Position Code）和鼠标激活返回值（MOUSEACTIVATE Return Codes）

//以下内容摘自 WinUser.h，仅为个人使用方便整理摘录至此。by:AsionTang

注：通过设置不同的鼠标位置编码，能够实现对C# 无边框窗体改变尺寸。

#ifndef NONCMESSAGES

/*
 * WM_NCHITTEST and MOUSEHOOKSTRUCT Mouse Position Codes
 */
#define HTERROR             (-2)
#define HTTRANSPARENT       (-1)
#define HTNOWHERE           0
#define HTCLIENT            1
#define HTCAPTION           2
#define HTSYSMENU           3
#define HTGROWBOX           4
#define HTSIZE              HTGROWBOX
#define HTMENU              5
#define HTHSCROLL           6
#define HTVSCROLL           7
#define HTMINBUTTON         8
#define HTMAXBUTTON         9
#define HTLEFT              10
#define HTRIGHT             11
#define HTTOP               12
#define HTTOPLEFT           13
#define HTTOPRIGHT          14
#define HTBOTTOM            15
#define HTBOTTOMLEFT        16
#define HTBOTTOMRIGHT       17
#define HTBORDER            18
#define HTREDUCE            HTMINBUTTON
#define HTZOOM              HTMAXBUTTON
#define HTSIZEFIRST         HTLEFT
#define HTSIZELAST          HTBOTTOMRIGHT
#if(WINVER >= 0x0400)
#define HTOBJECT            19
#define HTCLOSE             20
#define HTHELP              21
#endif /* WINVER >= 0x0400 */

#endif /* !NONCMESSAGES */

/*
 * WM_MOUSEACTIVATE Return Codes
 */
#define MA_ACTIVATE         1
#define MA_ACTIVATEANDEAT   2
#define MA_NOACTIVATE       3
#define MA_NOACTIVATEANDEAT 4