函数名: getmoderange 
 功  能: 取给定图形驱动程序的模式范围 
 用  法: #include <graphics.h> 
         void far getmoderange(int graphdriver, int far *lomode, int far *himode); 
 程序例: 
#include <graphics.h> 
 #include <stdlib.h> 
 #include <stdio.h> 
 #include <conio.h> 
int main(void) 
 { 
    /* request auto detection */ 
    int gdriver = DETECT, gmode, errorcode; 
    int midx, midy; 
    int low, high; 
    char mrange[80]; 
   /* initialize graphics and local variables */ 
    initgraph(&gdriver, &gmode, ""); 
   /* read result of initialization */ 
    errorcode = graphresult(); 
    if (errorcode != grOk)  /* an error occurred */ 
    { 
       printf("Graphics error: %s\n", grapherrormsg(errorcode)); 
       printf("Press any key to halt:"); 
       getch(); 
       exit(1); /* terminate with an error code */ 
    } 
   midx = getmaxx() / 2; 
    midy = getmaxy() / 2; 
   /* get the mode range for this driver */ 
    getmoderange(gdriver, &low, &high); 
   /* convert mode range info. into strings */ 
    sprintf(mrange, "This driver supports modes %d..%d", low, high); 
   /* display the information */ 
    settextjustify(CENTER_TEXT, CENTER_TEXT); 
    outtextxy(midx, midy, mrange); 
   /* clean up */ 
    getch(); 
    closegraph(); 
    return 0; 
 }