What are the best practices for replacing specific areas within a file before including it in PHP?

When including files in PHP, it may be necessary to replace specific areas within the file before including it to ensure that the content is customized for the current context. One common approach is to use placeholders in the file and then replace them with the desired values before including the file. This can be achieved using PHP's file_get_contents() function to read the file, str_replace() function to replace the placeholders, and eval() function to execute the modified content.

// Read the file content
$fileContent = file_get_contents('path/to/file.php');

// Replace placeholders with desired values
$fileContent = str_replace('{{placeholder1}}', $value1, $fileContent);
$fileContent = str_replace('{{placeholder2}}', $value2, $fileContent);

// Execute the modified content
eval('?>' . $fileContent);