In this article, we will learn about PHP constants. Constants are used to hold variables that remain constant during a program’s execution. They may be declared by using the keyword ‘const’ followed by the constant name. It should be noted that constant names in PHP are case-sensitive, however uppercase characters are preferred.
How to access the constant value within the class?
We can get the value of constant within the class using the self keyword, a scope resolution operator :: and the name of the constant. Look at the following example.
<?php
class hello {
const MESSAGE = "Thank you for visiting PHP.org";
}
echo hellp::MESSAGE;
?>How to access the constant value outside the class?
We can also get the value of the constant outside the class. Write the name of the class, scope resolution operator :: and the name of the constant.
<?php
class Hello {
const MESSAGE = "Thank you for visiting PHP.org";
public function tada() {
echo self::MESSAGE;
}
}
$hello= new hello();
$hello->tada();
?>
