declare array php

PHP
<?php
$array = array(
    "foo" => "bar",
    42    => 24,
    "multi" => array(
         "dimensional" => array(
             "array" => "foo"
         )
    )
);

var_dump($array["foo"]);
var_dump($array[42]);
var_dump($array["multi"]["dimensional"]["array"]);
?>

$tab = array(); // empty tab
$tab = array("0" => "Hello", "1" => "world"); // $tab[0]="hello" and $tab[1]="world"// sequential array
$arr = array(
  'v1',		// $arr[0] == 'v1'
  'v2',		// $arr[1] == 'v2'
  'v3'		// $arr[2] == 'v3'
);
// or (since PHP 5.4)
$arr = [
  'v1',		// $arr[0] == 'v1'
  'v2',		// $arr[1] == 'v2'
  'v3'		// $arr[2] == 'v3'
];

// key accessed array (map like)
$arr = array(
  'k1' => 'v1',		// $arr['k1'] == 'v1'
  'k2' => 'v2',		// $arr['k2'] == 'v2'
  'k3' => 'v3'		// $arr['k3'] == 'v3'
);
// or (since PHP 5.4)
$arr = [
  'k1' => 'v1',		// $arr['k1'] == 'v1'
  'k2' => 'v2',		// $arr['k2'] == 'v2'
  'k3' => 'v3'		// $arr['k3'] == 'v3'
];<?php
$cars = array("Volvo", "BMW", "Toyota");
echo "I like " . $cars[0] . ", " . $cars[1] . " and " . $cars[2] . ".";
?>#Arrays

<?php
    #array is a variable that holds multiple values
    /*
    Three types of arrays
        - Indexed
        - associative
        - Multi-dimensional
    */
    // Indexed array is the most common and easiest
    $people = array('Kevin', 'Jeremy ', 'Sara');
    $ids = array(23, 55, 12);
    $cars = ['Honda', ' Toyota', 'Ford'];  // also an array
    //add to an array
    $cars[3] = ' Audi';
    // you can use empty brackets and it will be added to the last one
    $cars[] = ' Chevy';

    echo $people[1];
    echo $ids[1];
    echo $cars[1];    
    echo $cars[3];
    echo $cars[4];
    echo count($cars);
    //you can also print the entire array
    print_r($cars);
    //to look at data type
    echo var_dump($cars);

    //Associative Arrays key pairs
    $people1 = array('Kevin' => 35, 'Jeremy' => 23, 'Sara' => 19);
    $ids1 = array(23 => 'Kevin', 55 => 'Jeremy', 12 => 'Sara');
    echo $people1['Kevin'];
    echo $ids1[23];
    //add to these types of arrays
    $people1['Jill'] = 44;
    echo $people1['Jill'];
    print_r($people1);
    var_dump($people1);

    //Multi-Dimensional Arrays aka an array within an array
 
    $cars2 = array(
        array('Honda',20,10),
        array('Toyota',30,20),
        array('Ford',23,12)
    );

    echo $cars2[1][0];

    
?>
Source

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