Php/docs/function.constant
constant
(PHP 4 >= 4.0.4, PHP 5, PHP 7)
constant — Returns the value of a constant
Description
constant
( string $name
) : mixed
Return the value of the constant indicated by
name.
constant() is useful if you need to retrieve the value of a constant, but do not know its name. I.e. it is stored in a variable or returned by a function.
This function works also with class constants.
Parameters
name- The constant name.
Return Values
Returns the value of the constant, or NULL if the constant is not
defined.
Errors/Exceptions
An E_WARNING level error is generated if the
constant is not defined.
Examples
Example #1 constant() example
<?phpdefine("MAXSIZE", 100);echo MAXSIZE;echo constant("MAXSIZE"); // same thing as the previous lineinterface bar { const test = 'foobar!';}class foo { const test = 'foobar!';}$const = 'test';var_dump(constant('bar::'. $const)); // string(7) "foobar!"var_dump(constant('foo::'. $const)); // string(7) "foobar!"?>
