C常用函數

檢查空格字符

#include <ctype.h>

int isspace ( int c );

http://www.cplusplus.com/reference/clibrary/cctype/isspace/

Checks if parameter c is a white-space character.For the purpose of this function, standard white-space characters are:

' '	(0x20)	space (SPC)
'/t'	(0x09)	horizontal tab (TAB)
'/n'	(0x0a)	newline (LF)
'/v'	(0x0b)	vertical tab (VT)
'/f'	(0x0c)	feed (FF)
'/r'	(0x0d)	carriage return (CR)

 /* isspace example */ #include <stdio.h> #include <ctype.h> int main () { int c; int i=0; char str[]="Example sentence to test isspace/n"; while (str[i]) { c=str[i]; if (isspace(c)) c='/n'; putchar (c); i++; } return 0; } /* This code prints out the C string character by character, replacing any white-space character by a newline character. Output: Example sentence to test isspace */

 

memcpy實現：

char *strcpy(char *strDest, const char *strSrc){ assert((strDest!=NULL) && (strSrc !=NULL)); // 2分 char *address = strDest; // 2分 while( (*strDest++ = * strSrc++) != '/0' ) // 2分 NULL ; return address ; // 2分 }