What is the difference between include() and require() functions in PHP?

The include() and require() functions in PHP perform the same function and can help us call files. So what's the difference between them? The following article will help you understand the difference between include() and require() functions. I hope it will be helpful to you. [Video tutorial recommendation: PHP tutorial]

##PHP include() function# The ##include() function is used to copy all the contents (text) within the file called within the function into the file calling it; this occurs before the server moves beyond the code.

Example: Use the include() function to call a file named demo.php

demo.php file:

<?php 
// 要包含的文件
echo "Hello PHP中文网！"；
?>

Now let us try to include this file into another php file (index.php). We will see the contents of the file displayed.

index.php file:

<?php  
header("content-type:text/html;charset=utf-8");
include("demo.php"); 
echo "<br>包含上述文件"
?>

Output:

##PHP require() function

The require() function performs the same operation as the include() function. It also fetches the required files and copies the entire code into the file where the require() function is called.

Example: Using the require() function to call a file named demo.php

demo.php file

<?php 
// 要包含的文件
echo "PHP中文网！"；
?>

Now, if we try to use the require() function to call this The file is included into the web page.

index.php file:

<?php  
header("content-type:text/html;charset=utf-8");
require("demo.php");
echo "<br>包含上述文件";
?>

Output:

##include() and require() functions The difference between

include() and require() functions have the same effect and produce the same results; but there is a difference between them. 1. When the called file is missing

●include() will display a warning (E_WARNING), but it will not stop script execution.

If we don't have a file named demo.php, then in case of include(), the following output will be shown with a warning about the missing file, but at least the output from the index.php file will be shown:

● require() will throw a fatal error (E_COMPILE_ERROR) because it cannot find the specific file at the specified location and therefore stops execution.

For the require() function, if the file contained in it (example: demo.php) is missing, a fatal error will occur, no output will be displayed, and execution will stop.

This is the main difference between include() and require() functions; but it also shows that require() function is better than include() function because if the file is missing or generated With this error, the script should not continue executing.

2. Loop or control structure

include() function can be used for loops or control structures. However, the require() function cannot be used with loops or control structures.

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