We are discussing some of the Win32 API to retrive some system paramerts and settings. We get verious Windows settings using GetSystemMetrics() function. GetDeviceCaps, GetTextMetrics, GetTextFace are the functions to retrieve the settings from screen and printer devices. Lets discuss these functions and see the utilities of these functions with one practical example for each.
The GetDeviceCaps function retrieves device-specific capabilities and information for the specified GDI device.
int GetDeviceCaps( HDC hdc, int nIndex );
Input & Output
Handle to the device context and the capability index number (see MSDN for list of capabilities). It returns the value of the corresponding capability.
Printer page dimension is 5100x6600 px Press any key to continue
Retrieves the specified system metric or system configuration setting.
int WINAPI GetSystemMetrics( int nIndex );
Input & Output
The system metric index which is required (see MSDN for list of values). It returns the value of the corresponding system parameter.
Primary desktop screen is 1366x768 px Press any key to continue
The GetTextMetrics function fills the specified buffer with the metrics for the currently selected font.
BOOL GetTextMetrics( HDC hdc, LPTEXTMETRIC lptm );
The GetTextFace function retrieves the typeface name of the font that is selected into the specified device context. Lenght of the string buffer and buffer pointer for retrieving the font name are given as the input.
int GetTextFace( HDC hdc, int nCount, LPTSTR lpFaceName );
GetTextMetrics GetTextFace example
Desktop font name is "System" font size = 16 Press any key to continue
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