c# api GetSystemMetrics
[DllImport("user32")]
public static extern int GetSystemMetrics(int nIndex);
nIndex值：
SM_CXSCREEN = 0 '屏幕宽度
SM_CYSCREEN = 1 '屏幕高度
SM_CXVSCROLL = 2 '垂直滚动条的宽度
SM_CYHSCROLL = 3 '水平滚动条的宽度
SM_CYCAPTION = 4 'Height of windows caption 实际标题高度加上SM_CYBORDER
SM_CXBORDER = 5 'Width of no-sizable borders 无法测量的窗口框架宽度
SM_CYBORDER = 6 'Height of non-sizable borders 无法测量的窗口框架高度
SM_CXDLGFRAME = 7 'Width of dialog box borders
SM_CYDLGFRAME = 8 'Height of dialog box borders
SM_CYHTHUMB = 9 'Height of scroll box on horizontal scroll bar 水平滚动条上滑块的高度
SM_CXHTHUMB = 10 ' Width of scroll box on horizontal scroll bar 水平滚动条上滑块的宽度
SM_CXICON = 11 'Width of standard icon 图标宽度
SM_CYICON = 12 'Height of standard icon 图标高度
SM_CXCURSOR = 13 'Width of standard cursor 光标宽度
SM_CYCURSOR = 14 'Height of standard cursor 光标高度
SM_CYMENU = 15 'Height of menu 以像素计算的单个菜单条的高度
SM_CXFULLSCREEN = 16 'Width of client area of maximized window
SM_CYFULLSCREEN = 17 'Height of client area of maximized window
SM_CYKANJIWINDOW = 18 'Height of Kanji window
SM_MOUSEPRESENT = 19 'True is a mouse is present 如果为TRUE或不为0的值则安装了鼠标，否则没有安装。
SM_CYVSCROLL = 20 'Height of arrow in vertical scroll bar
SM_CXHSCROLL = 21 'Width of arrow in vertical scroll bar
SM_DEBUG = 22 'True if deugging version of windows is running
SM_SWAPBUTTON = 23 'True if left and right buttons are swapped.
SM_CXMIN = 28 'Minimum width of window
SM_CYMIN = 29 'Minimum height of window
SM_CXSIZE = 30 'Width of title bar bitmaps
SM_CYSIZE = 31 'height of title bar bitmaps
SM_CXMINTRACK = 34 'Minimum tracking width of window
SM_CYMINTRACK = 35 'Minimum tracking height of window
SM_CXDOUBLECLK = 36 'double click width
SM_CYDOUBLECLK = 37 'double click height
SM_CXICONSPACING = 38 'width between desktop icons
SM_CYICONSPACING = 39 'height between desktop icons
SM_MENUDROPALIGNMENT = 40 'Zero if popup menus are aligned to the left of the memu bar item. True if it is aligned to the right.
SM_PENWINDOWS = 41 'The handle of the pen windows DLL if loaded.
SM_DBCSENABLED = 42 'True if double byte characteds are enabled
SM_CMOUSEBUTTONS = 43 'Number of mouse buttons.
SM_CMETRICS = 44 'Number of system metrics
SM_CLEANBOOT = 67 'Windows 95 boot mode. 0 = normal, 1 = safe, 2 = safe with network
SM_CXMAXIMIZED = 61 'default width of win95 maximised window
SM_CXMAXTRACK = 59 'maximum width when resizing win95 windows
SM_CXMENUCHECK = 71 'width of menu checkmark bitmap
SM_CXMENUSIZE = 54 'width of button on menu bar
SM_CXMINIMIZED = 57 'width of rectangle into which minimised windows must fit.
SM_CYMAXIMIZED = 62 'default height of win95 maximised window
SM_CYMAXTRACK = 60 'maximum width when resizing win95 windows
SM_CYMENUCHECK = 72 'height of menu checkmark bitmap
SM_CYMENUSIZE = 55 'height of button on menu bar
SM_CYMINIMIZED = 58 'height of rectangle into which minimised windows must fit.
SM_CYSMCAPTION = 51 'height of windows 95 small caption
SM_MIDEASTENABLED = 74 'Hebrw and Arabic enabled for windows 95
SM_NETWORK = 63 'bit o is set if a network is present.
SM_SECURE = 44 'True if security is present on windows 95 system
SM_SLOWMACHINE = 73 'true if machine is too slow to run win95.
