PHP Include and Require

PHP allows us to create various elements and functions, which are used several times in many pages. It takes much time to script these functions in multiple pages. Therefore, use the concept of file inclusion that helps to include files in various programs and saves the effort of writing code multiple times. "PHP allows you to include file so that a page content can be reused many times. It is very helpful to include files when you want to apply the same HTML or PHP code to multiple pages of a website." There are two ways to include file in PHP.

  1. include
  2. require

Both include and require are identical to each other, except failure.

Advantage

  • Code Reusability: By the help of include and require construct, we can reuse HTML code or PHP script in many PHP scripts.
  • Easy editable: If we want to change anything in webpages, edit the source file included in all webpage rather than editing in all the files .

    • PHP include

    PHP include is used to include a file on the basis of given path. You may use a relative or absolute path of the file.

    There are two syntaxes available for include:

    Syntax

    
include 'filename ';  
Or   
include ('filename');

    Let's see a simple PHP include example.

    File: menu.html

    PHP Example

    
<a href="http://www.javatpoint.com">Home</a>|     
<a href="http://www.javatpoint.com/php-tutorial">PHP</a> |     
<a href="http://www.javatpoint.com/java-tutorial">Java</a> |      
<a href="http://www.javatpoint.com/html-tutorial">HTML</a>

    File: include1.php

    PHP Example

    
?php include("menu.html"); ?>  
<h1>This is Main Page</h1>

    Output

    Home | PhP | Java | HTML This is Main Page

    PHP require

    PHP require is similar to include, which is also used to include files. The only difference is that it stops the execution of script if the file is not found whereas include doesn't.

    Syntax

    There are two syntaxes available for require:

    Syntax

    
require 'filename';  
Or   
require ('filename');

    Let's see a simple PHP require example.

    File: menu.html

    PHP Example

    
<a href="http://www.javatpoint.com">Home</a> |     
<a href="http://www.javatpoint.com/php-tutorial">PHP</a> |     
<a href="http://www.javatpoint.com/java-tutorial">Java</a> |      
<a href="http://www.javatpoint.com/html-tutorial">HTML</a>

    File: include1.php


    PHP Example

    
?php include("menu.html"); ?>  
<h1>This is Main Page</h1>

    Output

    Home | PhP | Java | HTML This is Main Page

    PHP include vs PHP require


    Both include and require are same. But if the file is missing or inclusion fails, include allows the script to continue but require halts the script producing a fatal E_COMPILE_ERROR level error. Let's understand the difference with the help of example:

    Example

    PHP Example

    
<?php   
//include welcome.php file   
include("welcome.php");  
echo "The welcome file is included.";  
?>

    Output

    The welcome.php file is not available in the same directory, which we have included. So, it will produce a warning about that missing file but also display the output. Warning: include(welcome.php): failed to open stream: No such file or directory in C:xampphtdocsprograminclude.php on line 3 Warning: include(): Failed opening 'welcome.php' for inclusion (include_path='C:xamppphpPEAR') in C:xampphtdocsprograminclude.php on line 3 The welcome file is included.

    PHP Example

    
<?php  
echo "HELLO";  
//require welcome.php file   
require("welcome.php");  
echo "The welcome file is required.";  
?>

    Output

    In case of require() if the file (welcome.php) is not found in the same directory. The require() will generate a fatal error and stop the execution of the script, as you can see in the below output. HELLO Warning: require(Welcome.php): failed to open stream: No such file or directory in C:xampphtdocsprograminclude.php on line 3