indexOf in PHP

PHP provides a function give the position of a particular char or a string with in a string, function which is equivalent to JAVA's indexOf method in PHP is strpos().
The strpos() function returns the position of the first occurrence of a string inside another string. If the string is not found, this function returns FALSE.

Method Signature

int strpos ( string $haystack , mixed $needle [, int $offset = 0 ] )

haystack : The string to search in.
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.
Returned Values : Returns the position as an integer. If needle is not found, strpos() will return boolean FALSE.

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";
}
?>

<?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'";
}
?>