PHP object-oriented-Introduction to the static binding function later-php instances

This article mainly introduces the PHP object-oriented static binding function later. This article will introduce the PHP static binding function later, which is mainly used to solve the class that references static calls within the inheritance scope, for more information about PHP static binding, see this article, It is mainly used to solve the class that references static calls within the inheritance scope..

First, let's look at the following example:

The Code is as follows:

Class Person
{

Public static function status ()
{
Self: getStatus ();
}

Protected static function getStatus ()
{
Echo "Person is alive ";
}

}

Class Deceased extends Person
{

Protected static function getStatus ()
{
Echo "Person is deceased ";
}

}

Deceased: status (); // Person is alive

Obviously, the result is not what we expected, because self: Depends on the class in the definition, rather than the class in the running. To solve this problem, you may rewrite the status () method in the inheritance class. A better solution is to add the static binding function after PHP 5.3.

The Code is as follows:

Class Person
{

Public static function status ()
{
Static: getStatus ();
}

Protected static function getStatus ()
{
Echo "Person is alive ";
}

}

Class Deceased extends Person
{

Protected static function getStatus ()
{
Echo "Person is deceased ";
}

}

Deceased: status (); // Person is deceased

It can be seen that static: does not point to the current class. In fact, it is calculated during running, and all attributes of the final class are forcibly obtained.

Therefore, we recommend that you do not use self: or static: in the future ::