分享给大家两个不区分大小写的字符串查找函数 strstr

char* stristr (
const char * str1,
const char * str2
)

{
char *cp = (char *) str1;
char *s1, *s2;

if ( !*str2 )
return((char *)str1);

while (*cp)
{
s1 = cp;
s2 = (char *) str2;

while (*s1 && *s2)
{
char ch1=*s1,ch2=*s2;
if (isascii(*s1) && isupper(*s1) ) ch1 = _tolower(*s1);
if (isascii(*s2) && isupper(*s2) ) ch2 = _tolower(*s2);

if(ch1-ch2==0) s1++, s2++;
else break;
}

if (!*s2)
return(cp);

cp++;
}

return(NULL);

}

WCHAR* wcsistr (
const WCHAR * str1,
const WCHAR * str2
)

{
WCHAR *cp = (WCHAR *) str1;
WCHAR *s1, *s2;

if ( !*str2 )
return((WCHAR *)str1);

while (*cp)
{
s1 = cp;
s2 = (WCHAR *) str2;

while (*s1 && *s2)
{
WCHAR ch1=*s1,ch2=*s2;
if (iswascii(*s1) && iswupper(*s1) ) ch1 = towlower(*s1);
if (iswascii(*s2) && iswupper(*s2) ) ch2 = towlower(*s2);

if(ch1-ch2==0) s1++, s2++;
else break;
}

if (!*s2)
return(cp);

cp++;
}

return(NULL);

}

//T函数申明

#ifdef UNICODE

# define _tcsistr wcsistr

#else

# define _tcsistr stristr

#endif