Passing Variables to Included Files in PHP

PHP provides a convenient way to include external files into scripts using the include statement. However, when trying to pass variables to included files, some users face challenges.

In older versions of PHP, it was necessary to explicitly pass variables using approaches like global variables or helper methods. However, in modern versions of PHP, this is no longer necessary.

Any PHP variable defined prior to calling include is automatically available in the included file. To illustrate this, consider the following example:

// In the main file:
$variable = "apple";
include('second.php');

// In second.php:
echo $variable; // Output: "apple"

This simple approach allows you to share variables between the main file and included files seamlessly.

It's important to note that if a variable is defined inside an included file, it will only be available within that file. To pass variables into a function that calls include inside, you can use the extract() function.

function includeWithVariables($filePath, $variables = [], $print = true)
{
    // Extract the variables to a local namespace
    extract($variables);

    // Start output buffering
    ob_start();

    // Include the template file
    include $filePath;

    // End buffering and return its contents
    $output = ob_get_clean();
    if (!$print) {
        return $output;
    }
    echo $output;
}

This allows you to pass variables to an included file while maintaining the flexibility of using a function.