Four PHP text functions strstr strrchr substr stristr

Note: If the string you want to find does not exist If found, then return FALSE. 2. stristr stristr — The function is the same as the strstr function, the only difference is that the case is ambiguous.

3. strrchr strrchr — Displays the last string found, the string to be found, and the subsequent strings.

Note: If The string to be searched for is not found, then FALSE is returned. 4. substr substr — In a string, truncate characters according to the given length. Format: string substr ( string $string , int $start [, int $length ] ) Parameter introduction: $string: the string to be intercepted; $start: The starting position to be intercepted, starting from 0 by default; if start is a negative number, the returned string will start from the $start character forward from the end of $string; if the length of string is less than or equal to start, will return FALSE. $length: The end position of interception. If $length is empty, then return from the starting position to the end.