Arrays¶

Indexed Arrays¶

<?php
$firstType = array("charles", "hello", "world", "Array");
$secondType = ["charles", "hello", "world", "Array"];
$allValues = [10, 1.3, "hello", true];
print_r($firstType);
echo "<br>";
print_r($secondType);
echo "<br>";
print_r($allValues);
?>

Associative Arrays¶

<?php
$authors = array(
"quarky" => "Charles Dickens",
10 => "Jane",
"poetic" => "William",
"Mark Twain"
);
print_r($authors);
//output:
//Array ( [quarky] => Charles Dickens [10] => Jane [poetic] => William [11] => Mark Twain )
?>

Note

Mark Twain will get an index of 11 which is an increment of the integer 10 that we have provided for Jane.

array_key_exists()¶

<?php
$firstType = array("charles", "hello", "world", "Array");
$authors = array(
"quarky" => "Charles Dickens",
"brilliant" => "Jane",
"poetic" => "William",
"Mark Twain"
);
echo $firstType[1]."<br>";
echo $authors["quarky"]."<br>";
echo array_key_exists(2, $firstType)."<br>";
echo array_key_exists("poetic", $authors);
//output:
//hello
//Charles Dickens
//1
//1
?>

in_array()¶

<?php
$firstType = array("charles", "hello", "world", "Array", 13);
echo in_array("charles", $firstType)."<br>";
echo in_array("charles", $firstType, true);
?>

Note

If value exist in array it will return 1 as true else it will return nothing as false
array function’s third parameter will indicate if the return type is the same as the search type ex. int == int
In this example if we search for 13 int will return true but string “13” will return false

array_push()¶

<?php
$authors = array("charles", "hello", "world", "Array", 13);
array_push($authors, "Louisa");
$authors[] = "Montgomery";
$authors["Hi"] = "Montgomery";
print_r($authors);
//output:
//Array ( [0] => charles [1] => hello [2] => world [3] => Array [4] => 13 [5] => Louisa [6] => Montgomery [Hi] => Montgomery )
?>

Note

There are two ways to add elements to an array which are array_push and $array[]=
The second method is prefered because if the array is not declared it will create a new array and add the value as the first parameter

aray_pop (remove lase item)¶

<?php
$authors = array("charles", "hello", "world", "Array");
$lastValue = array_pop($authors);
echo $lastValue."<br>";
print_r($authors);
//output:
//Array
//Array ( [0] => charles [1] => hello [2] => world )
?>

unset (delete arrray or element from array)¶

<?php
$first = array("charles", "hello", "world", "Array");
$second = array(
"quarky" => "Charles Dickens",
"brilliant" => "Jane",
"poetic" => "William",
"Mark Twain"
);
unset($first[1], $first[0]);
unset($second[brilliant]);
print_r($first);
echo "<br>";
unset($first);
print_r($first);
echo "<br>";
print_r($second);
?>

Sorting Arrays¶

sort()¶

<?php
$first = array("charles", "hello", "world", "Array");
$second = array(
"quarky" => "Charles Dickens",
"brilliant" => "Jane",
"poetic" => "William",
"Mark Twain"
);
sort($first);
print_r($first);
echo "<br>";
sort($second);
print_r($second);
//output:
//Array ( [0] => Array [1] => charles [2] => hello [3] => world )
//Array ( [0] => Charles Dickens [1] => Jane [2] => Mark Twain [3] => William )
?>

Note

index values will be reproduced for the sort results
by using sort in an associative array all associative key values will be changed int indexed value

asort()¶

<?php
$first = array("charles", "hello", "world", "Array");
$second = array(
"quarky" => "Charles Dickens",
"brilliant" => "Jane",
"poetic" => "William",
"Mark Twain"
);
asort($first);
print_r($first);
echo "<br>";
asort($second);
print_r($second);
//output:
////Array ( [3] => Array [0] => charles [1] => hello [2] => world )
//Array ( [quarky] => Charles Dickens [brilliant] => Jane [0] => Mark Twain [poetic] => William )
?>

Note

asort preserve original indexes and association array_key_exists

ksort()¶

<?php
$second = array(
"quarky" => "Charles Dickens",
"brilliant" => "Jane",
"poetic" => "William",
"Mark Twain"
);
ksort($second);
print_r($second);
//output:
//Array ( [brilliant] => Jane [poetic] => William [quarky] => Charles Dickens [0] => Mark Twain )
?>

Note

ksort will sort based on the index and associative key values

count()¶

<?php
$first = array("charles", "hello", "world", "Array");
echo count($first). "<br>";
$authors2 = [
        "Male" => array(
            "Charles" => array("Christmas Carol", "Oliver Twist"),
            "William" => array("Romeo & Juliet", "Richard III"),
            "Mark Twain" => Array("Tom Sawyer", "Huck Finn")
            ),
        "Female" => array(
            "L. M. Montgomery" => array("Anne of Green", "Anne of Avolea"),
            "Louisa May" => array("Litle Women")
            )
        ];
echo count($authors2)."<br>";
echo count($authors2, 1);
//output:
//4
//2
//16
?>

Note

In multi dimentional arrays we can use 1 or COUNT_RECURSIVE as a second parameter to count all alements of the arrays

foreach()¶

<?php
$second = array(
"quarky" => "Charles Dickens",
"brilliant" => "Jane",
"poetic" => "William",
"Mark Twain"
);
foreach($authors as $val)
{
    echo $val."<br>";
}
foreach($authors as $key => $val)
{
    echo $val."(".$key.")<br>";
}
//output:
//Charles Dickens
//Jane
//William
//Mark Twain
//Charles Dickens(quarky)
//Jane(brilliant)
//William(poetic)
//Mark Twain(0)
?>

Note

$key and $val are temporary variables

Multi dimentional array¶

<?php
$authors2 = [
        "Male" => array(
            "Charles" => array("Christmas Carol", "Oliver Twist"),
            "William" => array("Romeo & Juliet", "Richard III"),
            "Mark Twain" => Array("Tom Sawyer", "Huck Finn")
            ),
        "Female" => array(
            "L. M. Montgomery" => array("Anne of Green", "Anne of Avolea"),
            "Louisa May" => array("Litle Women")
            )
];
print_r($authors2['Male']['Mark Twain'][1]);
//output
//Huck Finn
?>

Note

Remove [] parameters to print previous level