如何在 php 中将 class 与命名空间一起使用？

Question

I try to create app with structure as below:

App
 +--src
      Example.php
 +--vendor
    --
 composer.json
 composer.lock
 index.php

Where Example.php set namespace Example then use it inside index.php . but it not working.

Example.php

<?php namespace Example

class Example {
    public function __construct()
    {
        echo 'constructed';
    }
}

index.php

<?php use Example\Example;

$example = new Example;

echo 'here ok';

but when I runing it in browser, its error:

This page isn't workinglocalhost is currently unable to handle this request.

What am I wrong, any help?

Answer 1

Since you haven't posted what your composer.json contains yet, at least you must have it in your autoload :

{
    "autoload": {
        "psr-4": {
            "Example\\": "src"
        }
    }
}

In your index.php , you need to require the autoload from composer:

require_once 'vendor/autoload.php'; // add the autoloader

use Example\Example;

$example = new Example;

echo 'here ok';

Lastly, you need to run composer to reflect your changes:

php composer dump-autoload