PHP array and array index

Array

(PHP 4, PHP 5, PHP 7)

array- Creating a new array

Descriptionarray array ([ mixed $... ])

Creates an array. For information on what an array is, read the array section.

Parameters

...

The syntax "index = values", separated by commas, defines the index and value. The index can be a string or a number. If the index is omitted, an integer index starting from 0 is automatically generated. If the index is an integer, the next resulting index will be the current largest integer index + 1. Note If you define two identical indexes, the next one overwrites the previous one.

Adding a comma after the last defined array item is not common, but it is a valid syntax.

return value

Returns an array created from a parameter. Parameters can be indexed with the- = operator. For information on what an array is, read the array section.

Example

The following example shows how to create a two-dimensional array, how to assign a key name to the corresponding array, and how to skip and continue the numeric index in a normal array.

Example #1 Array () example

<?php
$fruits = array (
    "fruits"  => array("a" => "orange", "b" => "banana", "c" => "apple"),
    "numbers" => array(1, 2, 3, 4, 5, 6),
    "holes"   => array("first", 5 => "second", "third")
);
?>

Example Automatic indexing of #2 array ()

<?php
$array = array(1, 1, 1, 1,  1, 8 => 1,  4 => 1, 19, 3 => 13);
print_r($array);
?>

The above routines will output:

Array (    [0] = 1    [1] = 1    [2] = 1    [3] =    [4] = 1    [8] = 1    [9] = 19)

Note that index 3 is defined two times and retains the last value of 13. Index 4 is defined after index 8, and the next auto-generated index (with a value of 19) is 9 because the largest index is 8.

This example establishes an array starting with 1.

Example #3 Array () indexed starting from 1

<?php
$firstquarter = array(1 => ‘January‘, ‘February‘, ‘March‘);
print_r($firstquarter);
?>

The above routines will output:

Array (    [1] = January    [2] = February    [3] = March)

In Perl, you can access the value of an array within double quotation marks. But in PHP you need to enclose the array in curly braces.

Example #4 access to arrays within double quotes

<?php

$foo = array(‘bar‘ => ‘baz‘);
echo "Hello {$foo[‘bar‘]}!"; // Hello baz!

?>

Comments

Note:

Array () is a language structure that is used to literally represent an array, not a regular function.

See

• Array_pad ()-fills the array with a value to a specified length
• List ()-assigns the values in the array to some variables
• COUNT ()-Calculates the number of cells in an array or the number of attributes in an object
• Range ()-Creates an array containing the specified range of cells
• Foreach
• The array type

PHP array and array index