那么如何在PHP中使类名全局化？

Question

I have a class called "user" with a function "createAccount". Within it I like to access another class via PostageApp::mail

But as this class is outside the scope it is not accessible. global seams to work for variables only. So how do I make a class name global?

include_once('../../ext_scripts/postageapp_class.inc');

class user {
  function createAccount(...) {
    global PostageApp;

    [...]

    $result = PostageApp::mail($mailTo, '', 'verify_email', array());
  }
}

Answer 1

The class have to be defined before you use it, so you have use require or require_once to include the file with your PostageApp class definition.

There is no notion of global for classes.

If you don't want to add the require , I advise you to look into autoloading .

Answer 2

If you are absolutely sure that the class has been defined in an included file, there is only one thing affecting its visibility in another file: I suppose the PostageApp class is in another namespace , as this is the only reason another class could have a different scope in PHP.

The keyword global is only necessary for global variables. Functions and classes are always accessible in any scope as soon as they have been declared.