strpos
(PHP 4, PHP 5)
strpos — Find position of first occurrence of a string
Description
Returns the numeric position of the first occurrence of needle in the haystack string. Unlike the strrpos() before PHP 5, this function can take a full string as the needle parameter and the entire string will be used.
Parameters
- haystack
-
- needle
-
If needle is not a string, it is converted to an integer and applied as the ordinal value of a character.
- offset
-
The optional offset parameter allows you to specify which character in haystack to start searching. The position returned is still relative to the beginning of haystack .
Return Values
Returns the position as an integer. If needle is not found, strpos() will return boolean FALSE.
Den här funktionen kan returnera det booleska värdet FALSE, men den kan också returnera ett icke-booleskt värde som är likvärdigt med FALSE, till exempel 0 eller "". Vänligen läs sektionen om booleska datatyper för mer information. Använd ===- operatorn för att testa returvärdet från den här funktionen.
Exempel
Example#1 strpos() examples
<?php
$mystring = 'abc';
$findme = 'a';
$pos = strpos($mystring, $findme);
// Note our use of ===. Simply == would not work as expected
// because the position of 'a' was the 0th (first) character.
if ($pos === false) {
echo "The string '$findme' was not found in the string '$mystring'";
} else {
echo "The string '$findme' was found in the string '$mystring'";
echo " and exists at position $pos";
}
// We can search for the character, ignoring anything before the offset
$newstring = 'abcdef abcdef';
$pos = strpos($newstring, 'a', 1); // $pos = 7, not 0
?>
Notes
Note: Den här funktionen är binär-säker.