PHP Magic Constant

PHP Magic Constant

There are a number of predefined constants available to your scripts.
We will use these constants as we need them; there’s a sample:

PHP: Magic Constant

PHP Magic Constant
__LINE__	The current line number of the file.
__FILE__	The full path and filename of the file.
__FUNCTION__	The function name
__CLASS__	The class name
__METHOD__	The class method name
PHP_VERSION	The PHP version
PHP_INT_MAX	The PHP integer value limit

__LINE__

The current line number of the file.

<?php echo "The Line number : ". __LINE__; ?>

1 2 3 4 5

<?php echo "The Line number : ". __LINE__; ?>

Output
The Line number : 2

__FILE__

The full path and filename of the file.

<?php echo "Your file name :". __FILE__; ?>

1 2 3 4 5

<?php echo  "Your file name :". __FILE__; ?>

Output
Your file name : C:xampplitehtdocsmagic_constantfile.php

__FUNCTION__,     __CLASS__,     __METHOD__

The function name
The class name
The class method name

<?php class demo { function test() { echo "Function of demo class : ". __FUNCTION__ ."<br/>"; } function testme() { echo "Method of demo class : ". __METHOD__ ."<br/>"; echo "Class : ". __CLASS__; } } $object=new demo(); $object->test(); $object->testme(); ?>

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33

<?php class demo { function test() { echo "Function of demo class : ". __FUNCTION__ ."<br/>"; } function testme() { echo "Method of demo class : ". __METHOD__ ."<br/>"; echo "Class : ". __CLASS__; } } $object=new demo(); $object->test(); $object->testme(); ?>

Output
Function of demo class : test
Method of demo class : demo::testme
Class : demo

PHP_VERSION

The PHP version

<?php echo "Current PHP Version you are using : ".PHP_VERSION; ?>

1 2 3 4 5

<?php echo "Current PHP Version you are using  : ".PHP_VERSION; ?>

Output
Current PHP Version you are using : 5.3.1

PHP_INT_MAX

The PHP integer value limit

<?php echo "Integer Maximum Value : ".PHP_INT_MAX; ?>

1 2 3 4 5

<?php echo "Integer Maximum Value : ".PHP_INT_MAX; ?>

Output
Integer Maximum Value : 2147483647