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PHP Manual for

strpos

(PHP 3, PHP 4 )

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, strpos() will return boolean FALSE .

Warning

This function may return Boolean FALSE , but may also return a non-Boolean value which evaluates to FALSE , such as 0 or "". Please read the section on Booleans for more information. Use the === operator for testing the return value of this function.

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
?>

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 .

See also strrpos(), stripos(), strripos(), strrchr(), substr(), stristr(), and strstr().

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