require_once

Syntax

bool require_once(
	string $file
);

PHP Manual

Description

This construct loads the specified file if that file exists. It will only load it one time. Therefore, if it’s called again, it checks in memory to determine if the file has already been loaded previously.

Unlike include, if the file does not exist, then a fatal E_COMPILE_ERROR error is thrown, which will halt the program from continuing.

The path can be omitted. In this case, PHP will search in the same directory for the file.

If the path is provided, whether it’s an absolute or relative path, PHP searches based upon that path.

The code contained within the loaded file will inherit the local variable scope on the line where it’s loaded.

Parameters

file

The file to be loaded.

Return Values

This function a true.