PHP · Theory

include & require

Theory

42/352

include & require

include 'header.php'; pastes that file here. If the file is missing, include warns and continues. require stops the page (fatal). require_once / include_once skip if already loaded — use for config.

Good for header/footer. Modern apps also use Composer autoload for classes.

Trap: include vs require on a missing config file — require is safer. Trap: path wrong relative to the current working directory.

Exam tip

require_once 'config.php'; include 'header.php';

Example

<?php
namespace App\\Util;

function add(int $a, int $b): int {
  return $a + $b;
}

echo \App\\Util\\add(2, 3);

include & require — namespaces organize code; require/include pull in files.

Short notes

Definclude/require pull another PHP file in.
Rulerequire if the file must exist. _once to avoid doubles.
TrapMissing config with include only.

PHP · Theory

include & require

← All stacks

Theory

42/352

include & require

Good for header/footer. Modern apps also use Composer autoload for classes.

Trap: include vs require on a missing config file — require is safer. Trap: path wrong relative to the current working directory.

Exam tip

require_once 'config.php'; include 'header.php';

Example

<?php
namespace App\\Util;

function add(int $a, int $b): int {
  return $a + $b;
}

echo \App\\Util\\add(2, 3);

include & require — namespaces organize code; require/include pull in files.

Short notes

Definclude/require pull another PHP file in.
Rulerequire if the file must exist. _once to avoid doubles.
TrapMissing config with include only.

include & require

Example

Short notes

Questions

include & require

Example

Short notes

Questions