PHP 字符串处理函数

字符串截取

string substr ( string $string , int $start [, int $length ] )
string mb_substr ( string $str , int $start [, int $length = NULL [, string $encoding =  mb_internal_encoding() ]] )

字符串长度

int strlen ( string $string ) mixed mb_strlen ( string $str [, string $encoding = mb_internal_encoding() ] )

大小写转换

string strtolower ( string $string ) string strtoupper ( string $string )

去除首尾空白字符

string trim ( string $str [, string $character_mask = " \t\n\r\0\x0B" ] ) string ltrim ( string $str [, string $character_mask ] ) string rtrim ( string $str [, string $character_mask ] )

查找字符串中某些字符首次出现位置

mixed strpos ( string $haystack , mixed $needle [, int $offset = 0 ] ) 
int mb_strpos ( string $haystack , string $needle [, int $offset = 0 [, string $encoding =  mb_internal_encoding() ]] )

字符串替换

mixed str_replace ( mixed $search , mixed $replace , mixed $subject [, int &$count ] )

重复字符串

string str_repeat ( string $input , int $multiplier )

字符串分割

array explode( string $input, string $char )