al13_3.c

里面告诉了许多你编程用的方法和例子

/*案例代码文件名：AL13_3.C*/
/*功能：检测图形显示卡的类型*/
#include "graphics.h"
char *devicename[]={"Autodetect","CGA","MCGA","EGA","EGA64","EGAMONO",
                           "RESERVED","HERCMONO","ATT400","VGA","PC3270"};
main()
     {int driver, mode;
      detectgraph(&driver, &mode);
      clrscr();
      if(driver == -2)
	   printf("There's no graphic adapter in the system\n");
      else
	   printf("You have %s video display card \n",devicename[driver]);
      printf("Press any key to continue!");
      getch();
      }