g.txt

C语言函数大全

exit(1); 
} maxx = getmaxx();
 maxy = getmaxy(); 

/* draw an image on the screen */ 
rectangle(0, 0, maxx, maxy); 
line(0, 0, maxx, maxy); 
line(0, maxy, maxx, 0); 
save_screen(ptr); /* save the current screen */ 
getch(); /* pause screen */ 
cleardevice(); /* clear screen */ 
restore_screen(ptr); /* restore the screen */ 
getch(); /* pause screen */ 
closegraph(); return 0; 
} 
void save_screen(void far *buf[4]) 
{ unsigned size; 
int ystart=0, yend, yincr, block; 
yincr = (maxy+1) / 4; 
yend = yincr; 
size = imagesize(0, ystart, maxx, yend); /* get byte size of image */ 
for (block=0; block<=3; block++) 
{ if ((buf[block] = farmalloc(size)) == NULL) 
{ closegraph(); 
printf("Error: not enough heap space in save_screen().\n"); 
exit(1); 
} 
getimage(0, ystart, maxx, yend, buf[block]); 
ystart = yend + 1; 
yend += yincr + 1; 
} 
} 

void save_screen(void far *buf[4]) 
{ 
unsigned size; 
int ystart=0, yend, yincr, block; 

yincr = (maxy+1) / 4; 
yend = yincr; 
size = imagesize(0, ystart, maxx, yend); /* get byte size of image */ 

for (block=0; block<=3; block++) 
{ 
if ((buf[block] = farmalloc(size)) == NULL) 
{ 
closegraph(); 
printf("Error: not enough heap space in save_screen().\n"); 
exit(1); 
} 
getimage(0, ystart, maxx, yend, buf[block]); 
ystart = yend + 1; 
yend += yincr + 1; 
} } 
void restore_screen(void far *buf[4]) 
{ 
int ystart=0, yend, yincr, block; 
yincr = (maxy+1) / 4; 
yend = yincr; 
for (block=0; block<=3; block++) 
{ 
putimage(0, ystart, buf[block], COPY_PUT); 
farfree(buf[block]); 
ystart = yend + 1; 
yend += yincr + 1; 
} 
} 
函数名: getlinesettings 
功 能: 取当前线型、模式和宽度 
用 法: void far getlinesettings(struct linesettingstype far *lininfo): 
程序例: 
#include <graphics.h> 
#include <stdlib.h> 
#include <stdio.h> 
#include <conio.h> 
/* the names of the line styles supported */ 
char *lname[] = { "SOLID_LINE", 
"DOTTED_LINE", 
"CENTER_LINE", 
"DASHED_LINE", 
"USERBIT_LINE" 
}; 
int main(void) 
{ /* request auto detection */ 
int gdriver = DETECT, gmode, errorcode; 
struct linesettingstype lineinfo; 
int midx, midy; 
char lstyle[80], lpattern[80], lwidth[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 information about current line settings */ 
getlinesettings(&lineinfo); 
/* convert line information into strings */ 
sprintf(lstyle, "%s is the line style.", 
lname[lineinfo.linestyle]); 
sprintf(lpattern, "0x%X is the user-defined line pattern.", 
lineinfo.upattern); 
sprintf(lwidth, "%d is the line thickness.", 
lineinfo.thickness); 
/* display the information */ 
settextjustify(CENTER_TEXT, CENTER_TEXT); 
outtextxy(midx, midy, lstyle); 
outtextxy(midx, midy+2*textheight("W"), lpattern); 
outtextxy(midx, midy+4*textheight("W"), lwidth); 
/* clean up */ 
getch(); 
closegraph(); 
return 0; 
} 



函数名: getmaxcolor 
功 能: 返回可以传给函数setcolor的最大颜色值 
用 法: int far getmaxcolor(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; 
char colstr[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; 
/* grab the color info. and convert it to a string */ 
sprintf(colstr, "This mode supports colors 0..%d", getmaxcolor()); 
/* display the information */ 
settextjustify(CENTER_TEXT, CENTER_TEXT); 
outtextxy(midx, midy, colstr); 
/* clean up */ 
getch(); 
closegraph(); 
return 0; 
} 
函数名: getmaxx 
功 能: 返回屏幕的最大x坐标 
用 法: int far getmaxx(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; 
char xrange[80], yrange[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; 

/* convert max resolution values into strings */ 
sprintf(xrange, "X values range from 0..%d", getmaxx()); 
sprintf(yrange, "Y values range from 0..%d", getmaxy()); 

/* display the information */ 
settextjustify(CENTER_TEXT, CENTER_TEXT); 
outtextxy(midx, midy, xrange); 
outtextxy(midx, midy+textheight("W"), yrange); 

/* clean up */ 
getch(); 
closegraph(); 
return 0; 
} 
函数名: getmaxy 
功 能: 返回屏幕的最大y坐标 
用 法: int far getmaxy(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; 
char xrange[80], yrange[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; 
/* convert max resolution values into strings */ 
sprintf(xrange, "X values range from 0..%d", getmaxx()); 
sprintf(yrange, "Y values range from 0..%d", getmaxy()); 
/* display the information */ 
settextjustify(CENTER_TEXT, CENTER_TEXT); 
outtextxy(midx, midy, xrange); 
outtextxy(midx, midy+textheight("W"), yrange); 
/* clean up */ 
getch(); 
closegraph(); 
return 0; 
} 
函数名: getmodename 
功 能: 返回含有指定图形模式名的字符串指针 
用 法: char *far getmodename(int mode_name); 
程序例: 
#include <graphics.h> 
#include <stdlib.h> 
#include <stdio.h> 
#include <conio.h> 
int main(void) 
{ 
/* request autodetection */ 
int gdriver = DETECT, gmode, errorcode; 
int midx, midy, mode; 
char numname[80], modename[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 mode number and name strings */ 
mode = getgraphmode(); 
sprintf(numname, "%d is the current mode number.", mode); 
sprintf(modename, "%s is the current graphics mode.", getmodename(mode)); 
/* display the information */ 
settextjustify(CENTER_TEXT, CENTER_TEXT); 
outtextxy(midx, midy, numname); 
outtextxy(midx, midy+2*textheight("W"), modename); 
/* clean up */ 
getch(); 
closegraph(); 
return 0; 
} 
函数名: getmoderange 
功 能: 取给定图形驱动程序的模式范围 
用 法: 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; 
} 
函数名: getpalette 
功 能: 返回有关当前调色板的信息 
用 法: void far getpalette(struct palettetype far *palette); 
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; 
struct palettetype pal; 
char psize[80], pval[20]; 
int i, ht; 
int y = 10; 
/* initialize graphics and local variables */ 
initgraph(&gdriver, &gmode, ""); 
/* read result of initialization */ 
errorcode = graphresult(); 
/* an error occurred */ 
if (errorcode != grOk) 
{ 
printf("Graphics error: %s\n", 
grapherrormsg(errorcode)); 
printf("Press any key to halt:"); 
getch(); 
/* terminate with an error code */ 
exit(1); 
} 
/* grab a copy of the palette */ 
getpalette(&pal); 
/* convert palette info. into strings */ 
sprintf(psize, "The palette has %d \ 
modifiable entries.", pal.size); 
/* display the information */ 
outtextxy(0, y, psize); 
if (pal.size != 0) 
{ ht = textheight("W"); 
y += 2*ht; 
outtextxy(0, y, "Here are the current \ 
values:"); 
y += 2*ht; 
for (i=0; i<pal.size; i++, y+=ht) 
{ sprintf(pval, 
"palette[%02d]: 0x%02X", i, 
pal.colors[i]); 
outtextxy(0, y, pval); 
} } 
/* clean up */ 
getch(); 
closegraph(); 
return 0; 
} 
函数名: getpass 
功 能: 读一个口令 
用 法: char *getpass(char *prompt); 
程序例: 
#include <conio.h> 
int main(void) 
{ char *password; 
password = getpass("Input a password:"); 
 cprintf("The password is: %s\r\n", password); 
return 0; 
} 




函数名: getpixel 
功 能: 取得指定像素的颜色 
用 法: int far getpixel(int x, int y); 
程序例: 

#include <graphics.h> 
#include <stdlib.h> 
#include <stdio.h> 
#include <conio.h> 
#include <dos.h> 

#define PIXEL_COUNT 1000 
#define DELAY_TIME 100 /* in milliseconds */ 
int main(void) 
{ /* request auto detection */ 
int gdriver = DETECT, gmode, errorcode; 
int i, x, y, color, maxx, maxy, 
maxcolor, seed; 
/* initialize graphics and local variables */ 
initgraph(&gdriver, &gmode, ""); 
/* read result of initialization */ 
errorcode = graphresult(); 
/* an error occurred */ 
if (errorcode != grOk) 
{ printf("Graphics error: %s\n", 
grapherrormsg(errorcode)); 
printf("Press any key to halt:"); 
getch(); 
/* terminate with an error code */ 
exit(1); 
} 
maxx = getmaxx() + 1; 
maxy = getmaxy() + 1; 
maxcolor = getmaxcolor() + 1; 
while (!kbhit()) { 
/* seed the random number generator */ 
seed = random(32767);