defined
(PHP 3, PHP 4 )
defined --
Checks whether a given named constant exists
Description
bool
defined ( string name)
Returns TRUE if the named constant given by
name has been defined,
FALSE otherwise.
Example 1. Checking Constants <?php
if (defined("CONSTANT")){ // Note that it should be quoted
echo CONSTANT; //
}
?> |
|
See also define(),
constant(),
get_defined_constants() and the section on
Constants.