Array Related Built-in Functions

PHP Tutorials - Herong's Tutorial Examples

∟Array Related Built-in Functions

This section provides a summary of built-in functions related arrays and some examples of how to use them.

PHP offers a number of interesting built-in functions to work with arrays:

array() - Creates a new array with default keys or with given keys.
array_combine() - Combines two arrays into a new array with the first array as keys and the second as values.
array_count_values() - Counts the frequencies of values in an array and returns them as an array.
array_key_exists() - Searches for a key in an array.
array_keys() - Returns an array with all keys of an array.
array_merge() - Merges two arrays into a single array.
array_pad() - Returns a copy of the array padded to size specified by size with value value.
array_pop() - Treats the array like a stack and pops the last value from the stack.
array_push() - Treats the array like a stack and pushes extra values to the end of the stack.
array_rand() - Returns the key for a random entry.
array_search() - Searches for a value in an array.
array_slice() - Extracts a slice of an given array.
array_shift() - Shifts the first value of the array off and returns it, shortening the array by one element and moving everything down.
array_values() - Returns an array with all values of an array.
count() - Returns Counts the elements of an array.
each() — Returns the current key and value pair from an array and advance the array cursor.
explode() - Splits a string into an array by a string. Deprecated in PHP 7.2.
min() - Returns the lowest value in that array.
max() - Returns the highest value in that array.
ksort() - Sorts an array by keys.
list() - Assigns array elements to variables.
range() - Creates an array containing a range of elements.
reset() - Rewinds array's internal pointer to the first element and returns the value of the first array element.
sort() - Sorts an array by values.
split() - Splits a string into an array by regular expression. Removed in PHP 7.3.

PHP also offers special loop statements to iterate over arrays:

foreach($myArray as $value) {}
foreach($myArray as $key=>$value) {}

Here is a simple script with a "foreach" statement:

<?php
#  ArrayLoop.php
#- Copyright 2003 (c) HerongYang.com. All Rights Reserved.
#
   print "\nLibrary hours:\n";
   $libraryHours = array(
      'Monday - Friday'=>'09:00 - 21:00',
      'Saturday'=>'09:00 - 17:00',
      'Sunday'=>'closed');
   foreach($libraryHours as $day=>$hours) {
      print "   $day: $hours\n";
   }
?>

Here is the output:

herong> \php\php ArrayLoop.php

Library hours:
   Monday - Friday: 09:00 - 21:00
   Saturday: 09:00 - 17:00
   Sunday: closed

Table of Contents

About This Book

Introduction and Installation of PHP

PHP Script File Syntax

PHP Data Types and Data Literals

Variables, References, and Constants

Expressions, Operations and Type Conversions

Conditional Statements - "if" and "switch"

Loop Statements - "while", "for", and "do ... while"

Function Declaration, Arguments, and Return Values

►Arrays - Ordered Maps

What Is an Array

Creating Arrays - Examples

►Array Related Built-in Functions

Usage Examples of Array Functions

Interface with Operating System

Introduction of Class and Object

Integrating PHP with Apache Web Server

Retrieving Information from HTTP Requests

Creating and Managing Sessions in PHP Scripts

Sending and Receiving Cookies in PHP Scripts

Controlling HTTP Response Header Lines in PHP Scripts

Managing File Upload

Functions to Manage Directories, Files and Images

Localization Overview of Web Applications

Using Non-ASCII Characters in HTML Documents

Using Non-ASCII Characters as PHP Script String Literals

Receiving Non-ASCII Characters from Input Forms

"mbstring" Extension and Non-ASCII Encoding Management

Managing Non-ASCII Character Strings with MySQL Servers

Configuring and Sending Out Emails

Managing PHP Engine and Modules on macOS

Managing PHP Engine and Modules on CentOS

Archived Tutorials

References

Full Version in PDF/EPUB