X
HOME HTML CSS JAVASCRIPT SQL PHP JQUERY XML ASP.NET MORE...
REFERENCES | EXAMPLES | FORUM | ABOUT

PHP define() Function

PHP Misc Reference PHP Misc Reference

Example

Define a case-sensitive constant:

<?php
define("GREETING","Hello you! How are you today?");
echo constant("GREETING");
?>

Run example »

Definition and Usage

The define() function defines a constant.

Constants are much like variables, except for the following differences:

  • A constant's value cannot be changed after it is set
  • Constant names do not need a leading dollar sign ($)
  • Constants can be accessed regardless of scope
  • Constant values can only be strings and numbers

Syntax

define(name,value,case_insensitive)

Parameter Description
name Required. Specifies the name of the constant
value Required. Specifies the value of the constant
case_insensitive Optional. Specifies whether the constant name should be case-insensitive. Possible values:
  • TRUE - Case-insensitive
  • FALSE - Default. Case-sensitive

Technical Details

Return Value: Returns TRUE on success or FALSE on failure
PHP Version: 4+


More Examples

Example 1

Define a case-insensitive constant:

<?php
define("GREETING","Hello you! How are you today?",TRUE);
echo constant("greeting");
?>

Run example »


PHP Misc Reference PHP Misc Reference

Your suggestion:

Close [X]

Thank You For Helping Us!

Your message has been sent to W3Schools.

Close [X]
Search w3schools.com:

WEB BUILDING

Download XML Editor FREE Website BUILDER Free HTML5 Templates

SHARE THIS PAGE

facebook