Comments are essential in programming as they help developers understand the code and make it more maintainable. In PHP, comments can be added to explain the logic, provide documentation, or disable certain parts of the code. There are two main ways to add comments in PHP: single-line comments and multi-line comments.
Single-line Comments
Single-line comments start with // and continue until the end of the line. They are ideal for adding short explanations or notes within the code. For example:
<?php
// This is a single-line comment
echo 'Hello, World!';
?>
Anything after // in a line is considered a comment and is ignored by the PHP interpreter.
Multi-line Comments
Multi-line comments start with /* and end with */. They can span multiple lines, making them suitable for longer explanations or commenting out large blocks of code. For example:
<?php
/*
This is a multi-line comment
It can span across multiple lines
*/
echo 'Hello, World!';
?>
Multi-line comments are useful for temporarily removing code during debugging or adding detailed documentation to a script.
Comments should be clear, concise, and relevant to the code they are describing. Over-commenting or leaving outdated comments can reduce the readability of the code. Therefore, it is essential to strike a balance and update comments as the code evolves.