(PHP 3, PHP 4 >= 4.0.0)

define -- Defines a named constant.


bool define (string name, mixed value [, bool case_insensitive])

Defines a named constant. See the section on constants for more details.

The name of the constant is given by name; the value is given by value.

The optional third parameter case_insensitive is also available. If the value TRUE is given, then the constant will be defined case-insensitive. The default behaviour is case-sensitive; i.e. CONSTANT and Constant represent different values.

Example 1. Defining Constants

define ("CONSTANT", "Hello world.");
echo CONSTANT; // outputs "Hello world."
echo Constant; // outputs "Constant" and issues a notice.

define ("GREETING", "Hello you.",TRUE);
echo GREETING; // outputs "Hello you."
echo Greeting; // outputs "Hello you."


define() returns TRUE on success and FALSE if an error occurs.

See also defined(), constant() and the section on Constants.