C语言函数大全G篇.docx

1、C语言函数大全G篇G：函数名: gcvt功 能: 把浮点数转换成字符串用 法: char *gcvt(double value, int ndigit, char *buf);程序例: #include #include int main(void) char str25; double num; int sig = 5; /* significant digits */ /* a regular number */ num = 9.876; gcvt(num, sig, str); printf(string = %sn, str); /* a negative number */ num

2、= -123.4567; gcvt(num, sig, str); printf(string = %sn, str); /* scientific notation */ num = 0.678e5; gcvt(num, sig, str); printf(string = %sn, str); return(0);函数名: geninterrupt功 能: 产生一个软中断用 法: void geninterrupt(int intr_num);程序例:#include #include /* function prototype */void writechar(char ch);int

3、main(void) clrscr(); gotoxy(80,25); writechar(*); getch(); return 0;/* outputs a character at the current cursor position using the video BIOS to avoid the scrolling of the screen when writing to location (80,25).*/void writechar(char ch) struct text_info ti; /* grab current text settings */ gettext

4、info(&ti); /* interrupt 0x10 sub-function 9 */ _AH = 9; /* character to be output */ _AL = ch; _BH = 0; /* video page */ _BL = ti.attribute; /* video attribute */ _CX = 1; /* repetition factor */ geninterrupt(0x10); /* output the char */函数名: getarccoords功 能: 取得最后一次调用arc的坐标用 法: void far getarccoords(

5、struct arccoordstype far *arccoords);程序例:#include #include #include #include int main(void)/* request auto detection */ int gdriver = DETECT, gmode, errorcode; struct arccoordstype arcinfo; int midx, midy; int stangle = 45, endangle = 270; char sstr80, estr80;/* initialize graphics and local variabl

6、es */ initgraph(&gdriver, &gmode, );/* read result of initialization */ errorcode = graphresult();/* an error occurred */ if (errorcode != grOk) printf(Graphics error: %sn, grapherrormsg(errorcode); printf(Press any key to halt:); getch();/* terminate with an error code */ exit(1); midx = getmaxx()

7、/ 2; midy = getmaxy() / 2;/* draw arc and get coordinates */ setcolor(getmaxcolor(); arc(midx, midy, stangle, endangle, 100); getarccoords(&arcinfo);/* convert arc information into strings */ sprintf(sstr, *- (%d, %d), arcinfo.xstart, arcinfo.ystart); sprintf(estr, *- (%d, %d), arcinfo.xend, arcinfo

8、.yend); /* output the arc information */ outtextxy(arcinfo.xstart, arcinfo.ystart, sstr); outtextxy(arcinfo.xend, arcinfo.yend, estr); /* clean up */ getch(); closegraph(); return 0;函数名: getaspectratio功 能: 返回当前图形模式的纵横比用 法: void far getaspectratio(int far *xasp, int far *yasp);程序例:#include #include #

9、include #include int main(void)/* request auto detection */ int gdriver = DETECT, gmode, errorcode; int xasp, yasp, midx, midy;/* initialize graphics and local variables */ initgraph(&gdriver, &gmode, );/* read result of initialization */ errorcode = graphresult();/* an error occurred */ if (errorco

10、de != grOk) printf(Graphics error: %sn, grapherrormsg(errorcode); printf(Press any key to halt:); getch();/* terminate with an error code */ exit(1); midx = getmaxx() / 2; midy = getmaxy() / 2; setcolor(getmaxcolor();/* get current aspect ratio settings */ getaspectratio(&xasp, &yasp);/* draw normal

11、 circle */ circle(midx, midy, 100); getch();/* draw wide circle */ cleardevice(); setaspectratio(xasp/2, yasp); circle(midx, midy, 100); getch();/* draw narrow circle */ cleardevice(); setaspectratio(xasp, yasp/2); circle(midx, midy, 100);/* clean up */ getch(); closegraph(); return 0;函数名: getbkcolo

12、r功 能: 返回当前背景颜色用 法: int far getbkcolor(void);程序例:#include #include #include #include #include int main(void) /* request auto detection */ int gdriver = DETECT, gmode, errorcode; int bkcolor, midx, midy; char bkname35;/* initialize graphics and local variables */ initgraph(&gdriver, &gmode, );/* read

13、result of initialization */ errorcode = graphresult();/* an error occurred */ if (errorcode != grOk) printf(Graphics error: %sn, grapherrormsg(errorcode); printf(Press any key to halt:); getch();/* terminate with an error code */ exit(1); midx = getmaxx() / 2; midy = getmaxy() / 2; setcolor(getmaxco

14、lor();/* for centering text on the display */ settextjustify(CENTER_TEXT, CENTER_TEXT);/* get the current background color */ bkcolor = getbkcolor();/* convert color value into a string */ itoa(bkcolor, bkname, 10); strcat(bkname, is the current background color.);/* display a message */ outtextxy(m

15、idx, midy, bkname);/* clean up */ getch(); closegraph(); return 0;函数名: getc功 能: 从流中取字符用 法: int getc(FILE *stream);程序例:#include int main(void) char ch; printf(Input a character:);/* read a character from the standard input stream */ ch = getc(stdin); printf(The character input was: %cn, ch); return 0

16、;函数名: getcbrk功 能: 获取Control_break设置用 法: int getcbrk(void);程序例:#include #include int main(void) if (getcbrk() printf(Cntrl-brk flag is onn); else printf(Cntrl-brk flag is offn); return 0;函数名: getch功 能: 从控制台无回显地取一个字符用 法: int getch(void);程序例:#include #include int main(void) char ch; printf(Input a char

17、acter:); ch = getche(); printf(nYou input a %cn, ch); return 0;函数名: getchar功 能: 从stdin流中读字符用 法: int getchar(void);程序例:#include int main(void) int c; /* Note that getchar reads from stdin and is line buffered; this means it will not return until you press ENTER. */ while (c = getchar() != n) printf(%

18、c, c); return 0;函数名: getche功 能: 从控制台取字符(带回显)用 法: int getche(void);程序例:#include #include int main(void) char ch; printf(Input a character:); ch = getche(); printf(nYou input a %cn, ch); return 0;函数名: getcolor功 能: 返回当前画线颜色用 法: int far getcolor(void);程序例:#include #include #include #include #include int

19、 main(void)/* request auto detection */ int gdriver = DETECT, gmode, errorcode; int color, midx, midy; char colname35;/* initialize graphics and local variables */ initgraph(&gdriver, &gmode, );/* read result of initialization */ errorcode = graphresult();/* an error occurred */ if (errorcode != grO

20、k) printf(Graphics error: %sn, grapherrormsg(errorcode); printf(Press any key to halt:); getch();/* terminate with an error code */ exit(1); midx = getmaxx() / 2; midy = getmaxy() / 2; setcolor(getmaxcolor();/* for centering text on the display */ settextjustify(CENTER_TEXT, CENTER_TEXT);/* get the

21、current drawing color */ color = getcolor();/* convert color value into a string */ itoa(color, colname, 10); strcat(colname, is the current drawing color.);/* display a message */ outtextxy(midx, midy, colname);/* clean up */ getch(); closegraph(); return 0;函数名: getcurdir功 能: 取指定驱动器的当前目录用 法: int ge

22、tcurdir(int drive, char *direc);程序例:#include #include #include char *current_directory(char *path) strcpy(path, X:); /* fill string with form of response: X: */ path0 = A + getdisk(); /* replace X with current drive letter */ getcurdir(0, path+3); /* fill rest of string with current directory */ ret

23、urn(path);int main(void) char curdirMAXPATH; current_directory(curdir); printf(The current directory is %sn, curdir); return 0;函数名: getcwd功 能: 取当前工作目录用 法: char *getcwd(char *buf, int n);程序例:#include #include int main(void) char bufferMAXPATH; getcwd(buffer, MAXPATH); printf(The current directory is:

24、 %sn, buffer); return 0;函数名: getdate功 能: 取DOS日期用 法: void getdate(struct *dateblk);程序例:#include #include int main(void) struct date d; getdate(&d); printf(The current year is: %dn, d.da_year); printf(The current day is: %dn, d.da_day); printf(The current month is: %dn, d.da_mon); return 0;函数名: getdef

25、aultpalette功 能: 返回调色板定义结构用 法: struct palettetype *far getdefaultpalette(void);程序例:#include #include #include #include int main(void)/* request auto detection */ int gdriver = DETECT, gmode, errorcode; int i;/* structure for returning palette copy */ struct palettetype far *pal=(void *) 0;/* initiali

26、ze graphics and local variables */ initgraph(&gdriver, &gmode, );/* read result of initialization */ errorcode = graphresult();/* an error occurred */ if (errorcode != grOk) printf(Graphics error: %sn, grapherrormsg(errorcode); printf(Press any key to halt:); getch();/* terminate with an error code */ exit(1); setcolor(getmaxcolor();/* return a pointer to the default palette */ pal = getdefaultpalette(); for (i=0; i16; i+