PHP Parse POST string to JSON object

gistfile1.aw

<?php

// Get the raw post string
$raw_post = @file_get_contents('php://input');

// Parse using json_decode
$post = json_decode($raw_post);

// $post now contains the JSON object

echo $post->from_address;
//: 'from_address@example.com'

?>

能解释一下吗