Hướng dẫn constants in php
Table of Contents
A constant is an identifier (name) for a simple value. As the name suggests, that value cannot change during the execution of the script (except for magic constants, which aren't actually constants). Constants are case-sensitive. By convention, constant identifiers are always uppercase.
The name of a constant follows the same rules as any label in PHP. A valid constant name starts with a letter or underscore, followed by any number of letters, numbers, or underscores. As a regular expression, it would be expressed thusly: It is possible to define() constants with reserved or even invalid names, whose value can only be retrieved with the constant() function. However, doing so is not recommended. Example #1 Valid and invalid constant names
Like superglobals, the scope of a constant is global. Constants can be accessed from anywhere in a script without regard to scope. For more information on scope, read the manual section on variable scope.
wbcarts at juno dot com ¶ 10 years ago
('MIN_VALUE', '0.0'); // RIGHT - Works OUTSIDE of a class definition.
warwick dot jm dot barnes at gmail dot com ¶ 2 years ago
ewspencer at industrex dot com ¶ 19 years ago
gried at NOSPAM dot nsys dot by ¶ 6 years ago
hafenator2000 at yahoo dot com ¶ 17 years ago
Andreas R. ¶ 15 years ago
Raheel Khan ¶ 7 years ago
MAX_VALUE = 10; Sumon Mahmud (Abu Taleb) ¶ 2 years ago
storm ¶ 17 years ago
DEBUG) {
jcastromail at yahoo dot es ¶ 4 years ago
mparsa1372 at gmail dot com ¶ 1 year ago
define('BOOK',100); php at webflips dot net ¶ 8 years ago
constant('echo'); // outputs 'My constant value' |