Usage Examples of Array Functions

This section provides usage examples of some commonly used array functions.



Here a PHP script that provides usage examples of some commonly used array functions:

<?php 
#  ArrayTips.php
#- Copyright (c) 2003-2019, HerongYang.com, All Rights Reserved.
# 

print("Empty array:\n");
$emptyArray = array();
print_r($emptyArray);
print("\n");

print("Array with default keys:\n");
$indexedArray = array("PHP", "Perl", "Java");
print_r($indexedArray);
print("\n");

print("Array with specified keys:\n");
$mappedArray = array("Zero"=>"PHP", "One"=>"Perl", "Two"=>"Java");
print_r($mappedArray);
print("\n");

print("Array with default keys:\n");
$indexedArray = array("PHP", "Perl", "Java");
$value = $indexedArray["1"];
print("The second value: $value\n");
print("\n");

print("Array with specified keys:\n");
$mappedArray = array("Zero"=>"PHP", "One"=>"Perl", "Two"=>"Java");
$value = $indexedArray["2"];
print("The third value: $value\n");
print("\n");

$languages = array();
$languages["Zero"] = "PHP";
$languages["One"] = "Perl";
$languages["Two"] = "Java";
print("Array with inserted values:\n");
print_r($languages);
print("\n");

$mixed = array();
$mixed["Zero"] = "PHP";
$mixed[1] = "Perl";
$mixed["Two"] = "Java";
$mixed["3"] = "C+";
$mixed[""] = "Basic";
print("Array with mixed keys:\n");
print_r($mixed);
print("\$mixed[3] = ".$mixed[3]."\n");
print("\$mixed[\"3\"] = ".$mixed["3"]."\n");
print("\$mixed[\"\"] = ".$mixed[""]."\n");
print("\n");

$mixed = array();
$mixed["Zero"] = "PHP";
$mixed[1] = "Perl";
$mixed["Two"] = "Java";
$mixed["3"] = "C+";
$mixed[""] = "Basic";
$mixed[] = "Pascal";
$mixed[] = "FORTRAN";
print("Array with default keys:\n");
print_r($mixed);
print("\n");

$oldArray = array("Zero"=>"PHP", "One"=>"Perl", "Two"=>"Java");
$newArray = $oldArray;
$refArray = <$oldArray;
$newArray["One"] = "Python";
$refArray["Two"] = "C#";
print("\$newArray[\"One\"] = ".$newArray["One"]."\n");
print("\$oldArray[\"One\"] = ".$oldArray["One"]."\n");
print("\$refArray[\"Two\"] = ".$refArray["Two"]."\n");
print("\$oldArray[\"Two\"] = ".$oldArray["Two"]."\n");
print("\n");

$array = array("Zero"=>"PHP", "One"=>"Perl", "Two"=>"Java");
$array["3"] = "C+";
$array[""] = "Basic";
$array[] = "Pascal";
$array[] = "FORTRAN";
print("Loop on value only:\n");
foreach ($array as $value) {
  print("$value, ");
}
print("\n\n");
print("Loop on key and value:\n");
foreach ($array as $key=>$value) {
  print("[$key] => $value\n");
}
print("\n");

$mixed = array();
$mixed["Two"] = "Java";
$mixed["3"] = "C+";
$mixed["Zero"] = "PHP";
$mixed[1] = "Perl";
$mixed[""] = "Basic";
$mixed[] = "Pascal";
$mixed[] = "FORTRAN";
$mixed["Two"] = "";
unset($mixed[4]); 
print("Order of array values:\n");
print_r($mixed);
print("\n");

$var = array(0,0,7);
print("Test 1: ". is_array($var)."\n");
$var = array();
print("Test 2: ". is_array($var)."\n");
$var = 1800;
print("Test 3: ". is_array($var)."\n");
$var = true;
print("Test 4: ". is_array($var)."\n");
$var = null;
print("Test 5: ". is_array($var)."\n");
$var = "PHP";
print("Test 6: ". is_array($var)."\n");
print("\n");

$array = array("PHP", "Perl", "Java");
print_r("Size 1: ".count($array)."\n");
$array = array();
print_r("Size 2: ".count($array)."\n");
print("\n");

$array = array("Zero"=>"PHP", "One"=>"Perl", "Two"=>"Java");
print("Is 'One' defined? ".array_key_exists("One", $array)."\n");
print("Is '1' defined? ".array_key_exists("1", $array)."\n");
print("Is 'Two' defined? ".isset($array["Two"])."\n");
print("Is '2' defined? ".isset($array[2])."\n");
print("\n");

$array = array("Perl", "PHP", "Java", "PHP");
print("Search 1: ".array_search("PHP",$array)."\n");
print("Search 2: ".array_search("Perl",$array)."\n");
print("Search 3: ".array_search("C#",$array)."\n");
print("\n");

$mixed = array();
$mixed["Zero"] = "PHP";
$mixed[1] = "Perl";
$mixed["Two"] = "Java";
$mixed["3"] = "C+";
$mixed[""] = "Basic";
$mixed[] = "Pascal";
$mixed[] = "FORTRAN";
$keys = array_keys($mixed);
print("Keys of the input array:\n");
print_r($keys);
print("\n");

$mixed = array();
$mixed["Zero"] = "PHP";
$mixed[1] = "Perl";
$mixed["Two"] = "Java";
$mixed["3"] = "C+";
$mixed[""] = "Basic";
$mixed[] = "Pascal";
$mixed[] = "FORTRAN";
$values = array_values($mixed);
print("Values of the input array:\n");
print_r($values);
print("\n");

$mixed = array();
$mixed["Zero"] = "PHP";
$mixed[1] = "Perl";
$mixed["Two"] = "Java";
$mixed["3"] = "C+";
$mixed[""] = "Basic";
$mixed[] = "Pascal";
$mixed[] = "FORTRAN";
sort($mixed);
print("Sorted by values:\n");
print_r($mixed);
print("\n");

$mixed = array();
$mixed["Zero"] = "PHP";
$mixed[1] = "Perl";
$mixed["Two"] = "Java";
$mixed["3"] = "C+";
$mixed[""] = "Basic";
$mixed[] = "Pascal";
$mixed[] = "FORTRAN";
ksort($mixed);
print("Sorted by keys:\n");
print_r($mixed);
print("\n");

$old = array();
$old["Zero"] = "PHP";
$old[1] = "Perl";
$old["Two"] = "Java";
$old["3"] = "C+";
$old[""] = "Basic";
$old[] = "Pascal";
$old[] = "FORTRAN";
$keys = array_keys($old);
$values = array_values($old);
print("Combined:\n");
$new = array_combine($keys, $values);
print_r($new);
print("\n");

print("Combined backward:\n");
$new = array_combine($values, $keys);
print_r($new);
print("\n");

$array = array("Google", "Yahoo", "Netscape");
list($first, $second, $third) = $array;
print("Test 1: The third site = $third\n");

# split() was DEPRECATED in PHP 5.3.0, and REMOVED in PHP 7.0.0
# list($month, $date, $year) = split("/","1/1/2006");
list($month, $date, $year) = explode("/","1/1/2006");
print("Test 2: Year = $year\n");
$array = array("Zero"=>"PHP", 1=>"Basic", "One"=>"Perl", 
  0=>"Pascal", 2=>"FORTRAN", "Two"=>"Java");
list($first, $second, $third) = $array;
print("Test 3: The third language = $third\n");
print("\n");

$lang = array("Perl", "PHP", "Java",);
$os = array("i"=>"Windows", "ii"=>"Unix", "iii"=>"Mac");
$mixed = array_merge($lang, $os);
print("Merged:\n");
print_r($mixed);
print("\n");

$waitingList = array();
array_push($waitingList, "Jeo");
array_push($waitingList, "Leo");
array_push($waitingList, "Kim");
$next = array_shift($waitingList);
array_push($waitingList, "Kia");
$next = array_shift($waitingList);
array_push($waitingList, "Sam");
print("Current waiting list:\n");
print_r($waitingList);
print("\n");

$waitingList = array();
array_push($waitingList, "Jeo");
array_push($waitingList, "Leo");
array_push($waitingList, "Kim");
$next = array_pop($waitingList);
array_push($waitingList, "Kia");
$next = array_pop($waitingList);
array_push($waitingList, "Sam");
print("Current waiting list:\n");
print_r($waitingList);
print("\n");

# each() was DEPRECATED as of PHP 7.2.0
# $array = array("Zero"=>"PHP", "One"=>"Perl", "Two"=>"Java");
# print("Loop with each():\n");  
# reset($array);
# while (list($key, $value) = each($array)) {
#   print("[$key] => $value\n");  
# }
# print("\n");  

print("Loop with current():\n");  
reset($array);
while ($value = current($array)) {
  print("$value\n");
  next($array);
}
print("\n");

print("Integers:\n");
$integers = range(1, 20, 3);
print_r($integers);
print("\n");

print("Characters:\n");
$characters = range("X", "c");
print_r($characters);
print("\n");

$array = array("Zero"=>"PHP", "One"=>"Perl", "Two"=>"Java");
$array = array_pad($array, 6, ">>");
$array = array_pad($array, -8, "---");
print("Padded:\n");
print(join(",", array_values($array)));
print("\n\n");

$array = array("Zero"=>"PHP", "One"=>"Perl", "Two"=>"Java");
$removed = array_splice($array, -2, 2);
print("Remaining chunk:\n");
print_r($array);
print("\n");
print("Removed chunk:\n");
print_r($removed);
print("\n");

$array = array(5, 7, 6, 2, 1, 3, 4, 2);
print("Minimum number: ".min($array)."\n");
print("Maximum number: ".max($array)."\n");
$array = array("Zero"=>"PHP", "One"=>"Perl", "Two"=>"Java");
print("Minimum string: ".min($array)."\n");
print("Maximum string: ".max($array)."\n");
print("\n");

$array = array("Hello!", "Hi!", "Allo!", "Hallo!", "Coucou!");
$key = array_rand($array);
print("Random greeting: ".$array[$key]."\n");
print("\n");
?>

Output of the above script:

C:\herong> \php\php ArrayTips.php

Empty array:
Array
(
)

Array with default keys:
Array
(
    [0] => PHP
    [1] => Perl
    [2] => Java
)

Array with specified keys:
Array
(
    [Zero] => PHP
    [One] => Perl
    [Two] => Java
)

Array with default keys:
The second value: Perl

Array with specified keys:
The third value: Java

Array with inserted values:
Array
(
    [Zero] => PHP
    [One] => Perl
    [Two] => Java
)

Array with mixed keys:
Array
(
    [Zero] => PHP
    [1] => Perl
    [Two] => Java
    [3] => C+
    [] => Basic
)
$mixed[3] = C+
$mixed["3"] = C+
$mixed[""] = Basic

Array with default keys:
Array
(
    [Zero] => PHP
    [1] => Perl
    [Two] => Java
    [3] => C+
    [] => Basic
    [4] => Pascal
    [5] => FORTRAN
)

$newArray["One"] = Python
$oldArray["One"] = Perl
$refArray["Two"] = C#
$oldArray["Two"] = C#

Loop on value only:
PHP, Perl, Java, C+, Basic, Pascal, FORTRAN,

Loop on key and value:
[Zero] => PHP
[One] => Perl
[Two] => Java
[3] => C+
[] => Basic
[4] => Pascal
[5] => FORTRAN

Order of array values:
Array
(
    [Two] =>
    [3] => C+
    [Zero] => PHP
    [1] => Perl
    [] => Basic
    [5] => FORTRAN
)

Test 1: 1
Test 2: 1
Test 3:
Test 4:
Test 5:
Test 6:

Size 1: 3
Size 2: 0

Is 'One' defined? 1
Is '1' defined?
Is 'Two' defined? 1
Is '2' defined?

Search 1: 1
Search 2: 0
Search 3:

Keys of the input array:
Array
(
    [0] => Zero
    [1] => 1
    [2] => Two
    [3] => 3
    [4] =>
    [5] => 4
    [6] => 5
)

Values of the input array:
Array
(
    [0] => PHP
    [1] => Perl
    [2] => Java
    [3] => C+
    [4] => Basic
    [5] => Pascal
    [6] => FORTRAN
)

Sorted by values:
Array
(
    [0] => Basic
    [1] => C+
    [2] => FORTRAN
    [3] => Java
    [4] => PHP
    [5] => Pascal
    [6] => Perl
)

Sorted by keys:
Array
(
    [] => Basic
    [Two] => Java
    [Zero] => PHP
    [1] => Perl
    [3] => C+
    [4] => Pascal
    [5] => FORTRAN
)

Combined:
Array
(
    [Zero] => PHP
    [1] => Perl
    [Two] => Java
    [3] => C+
    [] => Basic
    [4] => Pascal
    [5] => FORTRAN
)

Combined backward:
Array
(
    [PHP] => Zero
    [Perl] => 1
    [Java] => Two
    [C+] => 3
    [Basic] =>
    [Pascal] => 4
    [FORTRAN] => 5
)

Test 1: The third site = Netscape
Test 2: Year = 2006
Test 3: The third language = FORTRAN

Merged:
Array
(
    [0] => Perl
    [1] => PHP
    [2] => Java
    [i] => Windows
    [ii] => Unix
    [iii] => Mac
)

Current waiting list:
Array
(
    [0] => Kim
    [1] => Kia
    [2] => Sam
)

Current waiting list:
Array
(
    [0] => Jeo
    [1] => Leo
    [2] => Sam
)

Loop with current():
PHP
Basic
Perl
Pascal
FORTRAN
Java

Integers:
Array
(
    [0] => 1
    [1] => 4
    [2] => 7
    [3] => 10
    [4] => 13
    [5] => 16
    [6] => 19
)

Characters:
Array
(
    [0] => X
    [1] => Y
    [2] => Z
    [3] => [
    [4] => \
    [5] => ]
    [6] => ^
    [7] => _
    [8] => `
    [9] => a
    [10] => b
    [11] => c
)

Padded:
---,---,PHP,Perl,Java,>>,>>,>>

Remaining chunk:
Array
(
    [Zero] => PHP
)

Removed chunk:
Array
(
    [One] => Perl
    [Two] => Java
)

Minimum number: 1
Maximum number: 7
Minimum string: Java
Maximum string: Perl

Random greeting: Hello!

Last update: 2019.



 

Table of Contents

 About This Book

 Introduction and Installation of PHP 7.3

 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

 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

 MySQL Server Connection and Access Functions

 Functions to Manage Directories, Files and Images

 SOAP Extension Function and Calling Web Services

 SOAP Server Functions and Examples

 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

 Outdated Tutorials

 References

 Full Version in PDF/EPUB