Turbo C 2.0、Borland C++库函数及用例

Turbo C 2.0、Borland C++库函数及用例(11) 用 法: void far circle(int x, int y, int radius);
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 radius = 100; /* 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;
setcolor(getmaxcolor()); /* draw the circle */
circle(midx, midy, radius); /* clean up */
getch();
closegraph();
return 0;
}
函数名: cleardevice
功 能: 清除图形屏幕
用 法: void far cleardevice(void);
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; /* 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;
setcolor(getmaxcolor()); /* for centering screen messages */
settextjustify(CENTER_TEXT, CENTER_TEXT); /* output a message to the screen */
outtextxy(midx,midy,"press any key to clear the screen:"); /* wait for a key */
getch(); /* clear the screen */
cleardevice(); /* output another message */
outtextxy(midx, midy, "press any key to quit:"); /* clean up */
getch();
closegraph();
return 0;