When working with PHP, developers often need to include external files into their scripts. Two common methods for doing this are include() and file_get_contents(). Understanding the differences in performance and functionality between these two methods is crucial for optimizing your code.
Understanding the Problem
In PHP, include() is a construct used to incorporate the content of one PHP file into another, while file_get_contents() is a function that reads the entire contents of a file into a string. The question arises: Which of these methods is faster?
The Scenario
Let’s consider a situation where you need to include or read a PHP file, for instance, a configuration file or a library of functions. Here’s how you might typically use both approaches:
Original Code Examples
Using include():
include 'config.php';
Using file_get_contents():
$configContents = file_get_contents('config.php');
In this scenario, config.php is a file that might contain various configurations, functions, or variables that you need to access.
Performance Analysis
include()
- Functionality: The
include()statement not only reads the file but also executes any PHP code within that file. This is important because if the file contains functions, classes, or variable declarations, they become available in the scope of the calling file. - Overhead: Since
include()processes the code, it has an overhead compared to simply reading file contents. The execution of code may lead to performance bottlenecks if the included file is large or contains resource-intensive operations.
file_get_contents()
- Functionality: This function reads the file’s raw content into a string. Unlike
include(), it does not execute any PHP code within the file. Thus, it is purely a file-reading operation. - Overhead: Because
file_get_contents()only retrieves data without any processing, it typically operates faster thaninclude()for non-PHP files or when you do not need to execute the content.
Speed Comparison
- For simple file reads (especially of non-PHP files),
file_get_contents()is generally faster because it involves less overhead. - In contrast,
include()is necessary when you need to execute the file's PHP code, despite potentially being slower.
Example Insights
Imagine you have a configuration file that simply contains constant values. If you're only interested in the raw data, file_get_contents() is the better option for performance. However, if you need to call functions defined in that configuration, include() is necessary.
When to Use Each Function
-
Use
include(): When the file contains PHP code that you need to execute. For example, including a library of functions that will be used in your script. -
Use
file_get_contents(): When you only need to read the contents of a file as a string. Ideal for retrieving configuration settings that do not require execution, or when processing text files.
Conclusion
In summary, whether include() or file_get_contents() is faster depends on your needs. If you need to execute PHP code within the file, include() is required. However, if you simply want to read data, file_get_contents() is typically the faster and more efficient option.
Additional Resources
For further reading on performance optimization and file handling in PHP, consider checking out:
By understanding the differences and use cases of include() and file_get_contents(), you can make informed decisions that lead to better performance in your PHP applications.
