Multidimensional Arrays php

A multi-dimensional array each element in the main array can also be an array. And each element in the sub-array can be an array, and so on. Values in the multi-dimensional array are accessed using multiple index.

Example

In this example we create a two dimensional array to store marks of three students in three subjects:

This example is an associative array, you can create numeric array in the same fashion.

<html>
<body>
<?php
$marks = array(
"mohammad" => array
(
"physics" => 35,
"maths" => 30,
"chemistry" => 39
),
"qadir" => array
(
"physics" => 30,
"maths" => 32,
"chemistry" => 29
),
"zara" => array
(
"physics" => 31,
"maths" => 22,
"chemistry" => 39
)
);
/* Accessing multi-dimensional array values */
echo "Marks for mohammad in physics : " ;
echo $marks['mohammad']['physics'] . "<br />";
echo "Marks for qadir in maths : ";
echo $marks['qadir']['maths'] . "<br />";
echo "Marks for zara in chemistry : " ;
echo $marks['zara']['chemistry'] . "<br />";
?>
</body>
</html>

This will produce following result:

Marks for mohammad in physics : 35
Marks for qadir in maths : 32
Marks for zara in chemistry : 39

Counting multidimensional arrays

We touched briefly on multidimensional arrays in Creating Arrays in PHP Section. Essentially, a multidimensional array is an array whose elements are also arrays.

By default, count() only counts the elements in the top level of a multidimensional array. Here’s an example:

<?php

$movieInfo = array( "directors" => array( "Alfred Hitchcock", "Stanley Kubrick", "Martin Scorsese", "Fritz Lang" ),
"movies" => array( "Rear Window", "2001", "Taxi Driver", "Metropolis" ) );

// Displays "2"
echo count( $movieInfo );

?>

The above code only counts the 2 elements in the top-level array ("directors" and "movies").

If you want to count all the elements in a multidimensional array — that is, not just the top-level elements, but the elements in all arrays inside the array — then pass the constant COUNT_RECURSIVE as a second argument to count():

<?php

$movieInfo = array( "directors" => array( "Alfred Hitchcock", "Stanley Kubrick", "Martin Scorsese", "Fritz Lang" ),
"movies" => array( "Rear Window", "2001", "Taxi Driver", "Metropolis" ) );

// Displays "10"
echo count( $movieInfo, COUNT_RECURSIVE );

?>

In the above example, count() first counts the 2 elements in the top-level array ("directors" and "movies"). Then it counts all 8 elements in the nested arrays ("Alfred Hitchcock" to "Fritz Lang", then "Rear Window"to "Metropolis"). This results in a grand total of 10 elements.

Multidimensional Arrays php

Counting multidimensional arrays

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