strpos
(PHP 4, PHP 5)
strpos — Find the position of the first occurrence of a substring in a string
Descrierea
Find the numeric position of the first occurrence of
needle in the haystack string.
Parametri
-
haystack -
The string to search in.
-
needle -
If
needleis not a string, it is converted to an integer and applied as the ordinal value of a character. -
offset -
If specified, search will start this number of characters counted from the beginning of the string. Unlike strrpos() and strripos(), the offset cannot be negative.
Valorile întoarse
Returns the position of where the needle exists relative to the beginning of
the haystack string (independent of offset).
Also note that string positions start at 0, and not 1.
Returns FALSE if the needle was not found.
Această funcție poate întoarce valoarea Boolean FALSE, dar poate de
asemenea întoarce o valoare non-Boolean care evaluează în FALSE, cum ar fi
0 sau "". Vă rugăm să citiți secțiunea despre
tipul Boolean pentru mai multe
informații. Utilizați
operatorul === pentru a
verifica valoarea întoarsă de această funcție.
Exemple
Example #1 Using ===
<?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";
}
?>
Example #2 Using !==
<?php
$mystring = 'abc';
$findme = 'a';
$pos = strpos($mystring, $findme);
// The !== operator can also be used. Using != would not work as expected
// because the position of 'a' is 0. The statement (0 != false) evaluates
// to false.
if ($pos !== false) {
echo "The string '$findme' was found in the string '$mystring'";
echo " and exists at position $pos";
} else {
echo "The string '$findme' was not found in the string '$mystring'";
}
?>
Example #3 Using an offset
<?php
// We can search for the character, ignoring anything before the offset
$newstring = 'abcdef abcdef';
$pos = strpos($newstring, 'a', 1); // $pos = 7, not 0
?>
Note
Notă: Această funcție acceptă și date binare.
Vedeți de asemenea
- stripos() - Find the position of the first occurrence of a case-insensitive substring in a string
- strrpos() - Find the position of the last occurrence of a substring in a string
- strripos() - Find the position of the last occurrence of a case-insensitive substring in a string
- strstr() - Find the first occurrence of a string
- strpbrk() - Search a string for any of a set of characters
- substr() - Return part of a string
- preg_match() - Perform a regular expression match
