VC screen operations

The current screen resolution method obtained by vc is as follows:
1. Windows API call
Int width = GetSystemMetrics (SM_CXSCREEN );
Int height = GetSystemMetrics (SM_CYSCREEN );
To dynamically adapt to resolution changes, process the WM_DISPLAYCHANGE message.
2. Get resolution
BOOL EnumDisplaySettings (
LPCTSTR lpszDeviceName, // display device
DWORD iModeNum, // graphics mode
LPDEVMODE lpDevMode // graphics mode settings
);

Change resolution
LONG ChangeDisplaySettings (
LPDEVMODE lpDevMode, // graphics mode
DWORD dwflags // graphics mode options
);
3. Use GetDeviceCaps

Int GetDeviceCaps (
HDC hdc, // handle to the device context
Int nIndex // index of capability to query
);

4. Use GetDeviceCaps
HDC hdcScreen = GetDC (NULL );
Int cx = GetDeviceCaps (hdcScreen, HORZRES );
Int cy = GetDeviceCaps (hdcScreen, VERTRES );
DeleteObject (hdcScreen );
The nIndex can be used as follows:
Horzres vertres or
Respectively:
HORZRES: Width, in pixels, of the screen.
VERTRES: Height, in raster lines, of the screen.

That is, the device resolution.
5. Get the size of the desktop customer zone
(1) The simplest way to use APIs
RECT rc;
SystemParametersInfo (SPI_GETWORKAREA, 0, (PVOID) & rc, 0 );
Str. Format ("% d * % d", rc. Right-rc.left, rc. Bottom-rc.top );
(2) indirect calculation: first use the above three methods to get the screen size, and then subtract the taskbar size (note: Check whether the taskbar is hidden)
Int cx = GetSystemMetrics (SM_CXSCREEN );
Int cy = GetSystemMetrics (SM_CYSCREEN );
Or
HDC hdcScreen = GetDC (NULL );
Int cx = GetDeviceCaps (hdcScreen, HORZRES );
Int cy = GetDeviceCaps (hdcScreen, VERTRES );
DeleteObject (hdcScreen );

Taskbar:
CWnd * pTaskWnd = FindWindow (_ T ("Shell_TrayWnd"), NULL );
If (pTaskWnd) pTaskWnd-> ShowWindow (FALSE );
Hide the taskbar:
LONG lStyle = GetWindowLong (pTaskWnd-> GetSafeHwnd (), GWL_STYLE );
If (lStyle & WS_VISIBLE)
{ 
// Visible
} 
Else
{ 
// Hide
}

/////////////////////////////////
VC obtains the screen size
Int with = GetSystemMetrics (SM_CXFULLSCREEN );

Int heigh = GetSystemMetrics (SM_CYFULLSCREEN );

The two functions above show the screen size and do not include the taskbar and other areas.

Int cx = GetSystemMetrics (SM_CXSCREEN );
Int cy = GetSystemMetrics (SM_CYSCREEN );

The two functions obtain the real screen size.

The size obtained using the first two functions may be 1024*687, and the size obtained using the following two functions is 1024*768.
Description
Returns information related to windows.
Return value
Long depends on the constant index.
Parameter table
Parameter type and description
NIndex Long, constant, specifies the information to be obtained; as shown in the following table.
NIndex constant settings
Constant definition to obtain information
SM_ARRANGE sets how windows arranges a flag of the minimized window. Reference ARW constant in api32.txt
SM_CLEANBOOT specifies the startup mode. 0 = normal mode; 1 = security mode with network support
Number of available system environments of SM_CMETRICS
The number of SM_CMOUSEBUTTON buttons. Zero if there is no mouse
SM_CXBORDER, SM_CYBORDER size unchangeable border size
SM_CXCURSOR, SM_CYCURSOR standard pointer size
Size of the border in the SM_CXDLGFRAME and SM_CYDLGFRAME dialog boxes
SM_CXDOUBLECLK, SM_CYDOUBLECLK double-click the area size (refer to the annotation)
SM_CXFRAME, SM_CYFRAME variable border size (use SM_C? In win95 and nt 4.0? FIXEDFRAME)
SM_CXFULLSCREEN and SM_CYFULLSCREEN maximize the size of the window client area
Size of arrows on the SM_CXHSCROLL horizontal scroll bar
Size of SM_CXHTHUMB and SM_CYHTHUMB on the horizontal scroll bar
Size of SM_CXICON and SM_CYICON standard icons
The gap between SM_CXICONSPACING and SM_CYICONSPACING desktop icons. In win95 and nt 4.0, it refers to the distance between the big picture subject.
SM_CXMAXIMIZED and SM_CYMAXIMIZED maximize the default window size
SM_CXMAXTRACK, SM_CYMAXTRACK change window size, maximum track width
SM_CXMENUCHECK, SM_CYMENUCHECK
SM_CXMENUSIZE, the button size on the SM_CYMENUSIZE menu bar
Minimum size of SM_CXMIN and SM_CYMIN windows
SM_CXMINIMIZED: the SM_CYMINIMIZED minimized window must be filled with a rectangle smaller than or equal to SM_C? ICONSPACING
Minimum track width of the SM_CXMINTRACK and SM_CYMINTRACK windows
SM_CXSCREEN, SM_CYSCREEN screen size
SM_CXSIZE, SM_CYSIZE the size of the title bar bitmap
SM_CXSIZEFRAME, SM_CYSIZEFRAME has the size of the window in the WS_THICKFRAME style
Size of SM_CXSMICON and SM_CYSMICON icons
SM_CXSMSIZE, SM_CYSMSIZE the size of the title button
SM_CXVSCROLL, the size of the arrow button in the SM_CYVSCROLL vertical scroll bar
Height of SM_CYCAPTION window title
Size of the SM_CYKANJIWINDOW Kanji window (Height of Kanji window)
SM_CYMENU menu height
Height of SM_CYSMCAPTION subtitles
Height of the scroll block on the SM_CYVTHUMB vertical scroll bar
SM_DBCSENABLED: TRUE if dual bytes are supported
If the debug version of windows is running, the value of SM_DEBUG is TRUE.
SM_MENUDropALIGNMENT. If the pop-up menu is aligned to the left of the menu bar item, the value is zero.
SM_MIDEASTENABLED allows Hebrew and Arabic
SM_MOUSEPRESENT: TRUE if the mouse is installed
SM_MOUSEWHEELPRESENT: TRUE if the mouse with a wheel is installed; applicable only to nt 4.0
If SM_NETWORK is installed with a network, set the bit to 0. Other places are retained
SM_PENWINDOWS indicates the handle of the pen window if the DLL supporting the Pen Window is loaded.
SM_SECURE is TRUE if the secure (confidential) mechanism is installed.
SM_SHOWSOUNDS forces visual display of sound
The SM_SLOWMACHINE System is too slow but is still running (System is too slow for failed use but is being run anyway)
SM_SWAPBUTTON. If the left and right mouse buttons have been switched, the value is TRUE.
Annotation
Double-click an area to specify a specific display area on the screen. It can be processed as a double-click event only when two consecutive mouse clicks are made in this area.
Others
Constant SM_ARRANGE, SM_CLEANBOOT, SM_CMETRICS, SM_C? MAXIMIZED, SM_C? MAXTRACK, SM_C? SIZEFRAME, SM_C? SMICON, SM_C? SMSIZE, SM_CYSMCAPTION,
SM_SECURE, SM_SHOWSOUNDS, and SM_SLOWMACHINE are not supported by NT 3.51 or earlier versions.

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VC screen operations