Protected and const attributes of php classes and objects

This article introduces the use of the protected and const attributes of classes and objects in php. For more information, see The const attribute. The field defined by the const attribute is a constant.

This article introduces the use of protected and const attributes of classes and objects in php. For more information, see.

Const attributes

The field defined with the const attribute is a constant. constants in the class are similar to static variables. The difference is that the value of a constant cannot be changed once it is assigned a value. the const definition constant does not require the $ symbol. its structure is as follows:

Const constant name // constant name cannot use the $ symbol

The instance code is as follows: