PHP define() Function
Example
Define a case-sensitive constant:
<?php
define("GREETING","Hello you! How are you today?");
echo constant("GREETING");
?>
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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:
|
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");
?>
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PHP Misc Reference