strpos -- Find position of first occurrence of a string
Description
int strpos ( string haystack, string needle [, int offset])
Returns the numeric position of the first occurrence of needle in the haystack string. Unlike the strrpos(), this function can take a full string as the needle parameter and the entire string will be used.
If needle is not found, returns FALSE.
注: It is easy to mistake the return values for "character found at position 0" and "character not found". Here's how to detect the difference:
// in PHP 4.0b3 and newer:
$pos = strpos($mystring, "b");
if ($pos === false) { // note: three equal signs
// not found...
}
// in versions older than 4.0b3:
$pos = strpos($mystring, "b");
if (!is_integer($pos)) {
// not found...
}
If needle is not a string, it is converted to an integer and applied as the ordinal value of a character.
The optional offset parameter allows you to specify which character in haystack to start searching. The position returned is still relative to the the beginning of haystack.