PHP constant()Functions

PHP Misc 参考手册PHP Misc Reference Manual

Examples

Returns the value of a constant:

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

echo constant("GREETING");
?>

Run example »

Definition and Usage

The constant() function returns the value of a constant.

Note:This function also works for class constants.


Syntax

constant(constant)

Parameter Description
constant Required. Specifies the name of the constant to check.

Technical Details

Return value: Returns the value of the constant, or NULL if the constant is not defined.
PHP Version: 4+


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