Summary - File inclusion

PHP course · Beginner · Lesson 111/116

Build a simple site skeleton with include, __DIR__ and partials.

Summary - File inclusion

In this group you saw the four statements for file inclusion in PHP: include continues with a warning, require raises a fatal error, include_once and require_once include a file only once. When you build paths with __DIR__, the script runs correctly from any directory.

With these tools you can combine partial files (header, footer, content) into consistent page layouts. On large sites every page shares the same skeleton; a change is made in a single partial. In the next section you will see require_once again for OOP and class autoloading.

Exercise Combine header, content and footer partials in a layout

Assign sys_get_temp_dir() to $dir. Create $dir . "/header.php", $dir . "/content.php" and $dir . "/footer.php" with file_put_contents; the contents are "<?php echo 'HEADER'; ?>", "<?php echo 'CONTENT'; ?>", "<?php echo 'FOOTER'; ?>" in order. Then write, in order, require $dir . "/header.php";, echo " ";, include $dir . "/content.php";, echo " ";, require $dir . "/footer.php";.

Show example solution

First set $dir = sys_get_temp_dir();. Write header.php, content.php and footer.php with file_put_contents. Then add require $dir . "/header.php";, echo " ";, include $dir . "/content.php";, echo " ";, require $dir . "/footer.php";.
Example solution:
<?php
// Create header, content and footer partials and combine in a layout
$dir = sys_get_temp_dir();
file_put_contents($dir . "/header.php", "<?php echo 'HEADER'; ?>");
file_put_contents($dir . "/content.php", "<?php echo 'CONTENT'; ?>");
file_put_contents($dir . "/footer.php", "<?php echo 'FOOTER'; ?>");
require $dir . "/header.php";
echo " ";
include $dir . "/content.php";
echo " ";
require $dir . "/footer.php";

Test yourself

Match statements to their features

include

Continues with warning
require

Stops with fatal error
include_once

Once, warns
__DIR__

Absolute directory path

Require the must-have file

require __DIR__ . '/____.php';

Show answer

require __DIR__ . '/config.php';

Which statement stops the script when a file is missing?
- include
- include_once
- require
- echo
Show answer

require — Correct. require raises a fatal error and stops the script when the file is missing.

Summary - File inclusion