PHP array indexof code example

Example 1: get key of value array php

<?php
$array = array(0 => 'blue', 1 => 'red', 2 => 'green', 3 => 'red');

$key = array_search('green', $array); // $key = 2;
$key = array_search('red', $array);   // $key = 1;
?>

Example 2: php indexof

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

Example 3: php array get value at index

$array = array('foo' => 'bar', 33 => 'bin', 'lorem' => 'ipsum');
$array = array_values($array);
echo $array[0]; //bar
echo $array[1]; //bin
echo $array[2]; //ipsum

Example 4: php indexof

strrpos ( string $haystack , mixed $needle [, int $offset = 0 ] ) : int or False return
<?php
$foo = "0123456789a123456789b123456789c";

// Looking for '0' from the 0th byte (from the beginning)
var_dump(strrpos($foo, '0', 0));

// Looking for '0' from the 1st byte (after byte "0")
var_dump(strrpos($foo, '0', 1));

$str = 'This is Main String';
 
if (strpos($str, 'This') !== false) {
    echo 'true';
}