Menu
×
   ❮     
HTML CSS JAVASCRIPT SQL PYTHON JAVA PHP HOW TO W3.CSS C C++ C# BOOTSTRAP REACT MYSQL JQUERY EXCEL XML DJANGO NUMPY PANDAS NODEJS R TYPESCRIPT ANGULAR GIT POSTGRESQL MONGODB ASP AI GO KOTLIN SASS VUE DSA GEN AI SCIPY AWS CYBERSECURITY DATA SCIENCE
     ❯   

PHP Tutorial

PHP HOME PHP Intro PHP Install PHP Syntax PHP Comments PHP Variables PHP Echo / Print PHP Data Types PHP Strings PHP Numbers PHP Casting PHP Math PHP Constants PHP Magic Constants PHP Operators PHP If...Else...Elseif PHP Switch PHP Loops PHP Functions PHP Arrays PHP Superglobals PHP RegEx

PHP Forms

PHP Form Handling PHP Form Validation PHP Form Required PHP Form URL/E-mail PHP Form Complete

PHP Advanced

PHP Date and Time PHP Include PHP File Handling PHP File Open/Read PHP File Create/Write PHP File Upload PHP Cookies PHP Sessions PHP Filters PHP Filters Advanced PHP Callback Functions PHP JSON PHP Exceptions

PHP OOP

PHP What is OOP PHP Classes/Objects PHP Constructor PHP Destructor PHP Access Modifiers PHP Inheritance PHP Constants PHP Abstract Classes PHP Interfaces PHP Traits PHP Static Methods PHP Static Properties PHP Namespaces PHP Iterables

MySQL Database

MySQL Database MySQL Connect MySQL Create DB MySQL Create Table MySQL Insert Data MySQL Get Last ID MySQL Insert Multiple MySQL Prepared MySQL Select Data MySQL Where MySQL Order By MySQL Delete Data MySQL Update Data MySQL Limit Data

PHP XML

PHP XML Parsers PHP SimpleXML Parser PHP SimpleXML - Get PHP XML Expat PHP XML DOM

PHP - AJAX

AJAX Intro AJAX PHP AJAX Database AJAX XML AJAX Live Search AJAX Poll

PHP Examples

PHP Examples PHP Compiler PHP Quiz PHP Exercises PHP Server PHP Syllabus PHP Certificate

PHP Reference

PHP Overview PHP Array PHP Calendar PHP Date PHP Directory PHP Error PHP Exception PHP Filesystem PHP Filter PHP FTP PHP JSON PHP Keywords PHP Libxml PHP Mail PHP Math PHP Misc PHP MySQLi PHP Network PHP Output Control PHP RegEx PHP SimpleXML PHP Stream PHP String PHP Variable Handling PHP XML Parser PHP Zip PHP Timezones

PHP Comments


Comments in PHP

A comment in PHP code is a line that is not executed as a part of the program. Its only purpose is to be read by someone who is looking at the code.

Comments can be used to:

  • Let others understand your code
  • Remind yourself of what you did - Most programmers have experienced coming back to their own work a year or two later and having to re-figure out what they did. Comments can remind you of what you were thinking when you wrote the code
  • Leave out some parts of your code

PHP supports several ways of commenting:

Example

Syntax for comments in PHP code:

// This is a single-line comment

# This is also a single-line comment

/* This is a
multi-line comment */
Try it Yourself »

Single Line Comments

Single line comments start with //.

Any text between // and the end of the line will be ignored (will not be executed).

You can also use # for single line comments, but in this tutorial we will use //.

The following examples uses a single-line comment as an explanation:

Example

A comment before the code:

// Outputs a welcome message:
echo "Welcome Home!";
Try it Yourself »

Example

A comment at the end of a line:

echo "Welcome Home!"; // Outputs a welcome message
Try it Yourself »

Comments to Ignore Code

We can use comments to prevent code lines from being executed:

Example

Do not display a welcome message:

// echo "Welcome Home!";
Try it Yourself »


×

Contact Sales

If you want to use W3Schools services as an educational institution, team or enterprise, send us an e-mail:
[email protected]

Report Error

If you want to report an error, or if you want to make a suggestion, send us an e-mail:
[email protected]

W3Schools is optimized for learning and training. Examples might be simplified to improve reading and learning. Tutorials, references, and examples are constantly reviewed to avoid errors, but we cannot warrant full correctness of all content. While using W3Schools, you agree to have read and accepted our terms of use, cookie and privacy policy.

Copyright 1999-2024 by Refsnes Data. All Rights Reserved. W3Schools is Powered by W3.CSS.