php命名空间详解

index.php:
<?php
include 'demo.php';
use A\demo as test;
use B\demo as test2;
use C\demo;

$obj = new test();

$obj = new test2();
echo B\b."<br>";

class c extends demo{

}

$obj = new c();
$obj -> say();

demo:php
<?php
namespace A;
class demo{
    public function __construct(){
        echo __NAMESPACE__."<br>";
    }
}

namespace B;
const b = 'I am in namespace B';
class demo{
    public function __construct() {
        echo __NAMESPACE__."<br>";
    }
}

namespace C;
class demo{
    public function say(){
        echo 'Class C say...';
    }
}