如何通过PHP中的POST在网页之间传递对象？

Question

Is it possible to pass an Object through a Hidden Field in an HTML Form using $_POST and retrieve that Object on the page that the form links to?

On the first page, I have a form like the one below:

<?php
session_start();
require_once '../Model/player.php'; // To Enable Creation of a New Player Object

$playerName = filter_input(INPUT_POST, 'playerName');
$playerNumber = 1;

$player = new player($playerName, $playerNumber);

if (isset($player))
{
  echo '<p>Successfully created your player!</p><br>';
?>

<form class="viewStats" action="../View/displayPlayerStatsView.php" method="post">
  <input type="hidden" name="playerObject" value="<?php echo $player; ?>">
  <input type="submit" value="View Your Player's Stats">
</form>

<?php
  }
?>

And on the second (receiving) page, I have code like the code below:

session_start();
require_once '../Model/player.php'; // To Use Player Object

$player = filter_input(INPUT_POST, 'playerObject'); // ERROR: Thinks the Player Object is a string.

My error seems to be that the receiving page that retrieves the 'playerObject' from the $_POST array is acting like the Object is a string.

Can anyone give me guidance on how to pass an Object from one page to another using the $_POST array? Is this even possible? Thank you in advance.

UPDATE: Based on suggestions to serialize the Object, I now am getting the following errors:

If I change my code on the first (sending) page to:

$playerSerial = serialize((object) $player);
<form class="viewStats" action="../View/displayPlayerStatsView.php" method="post">
      <input type="hidden" name="playerObject" value="<?php echo $playerSerial; ?>">
      <input type="submit" value="View Your Player's Stats">
</form>

and change the code on the second (receiving) page to:

$playerSerial = filter_input(INPUT_POST, 'playerObject');
print_r($playerSerial);
$player = unserialize($playerSerial);

then the output I get from print_r($playerSerial); is O:6: , which I know is incorrect since the object has properties holding a player's name, number, health, strength, etc.

The require_once '../Model/player.php'; code exists in both PHP files, and it comes right at the top of both before any other code is executed.

Answer 1

You have to make a few additions and corrections:

<?php 

//... your previous code

$player = serialize($player);
?>

<form class="viewStats" action="../View/displayPlayerStatsView.php" method="post">
  <input type="hidden" name="playerObject" value="<?php echo $player; ?>">
  <input type="submit" value="View Your Player's Stats">
</form>

Use the serialize() function to create a string that can be passed to your other page which you can unserialize() as follows:

secondPage.php:

$player = $_POST['playerObject'];
$player = unserialize($player);

Also, you forgot to use echo here:

change

value="<?php $player ?>"

to

value="<?php echo $player; ?>"

Answer 2

Get yourself into serialization: the process of making a string from the object, which can in future be deserialized from the string back to object.

Some docs, which could be useful for you:

PHP - How object serialize/unserialize works?

http://php.net/manual/ru/oop4.serialization.php

http://www.phpinternalsbook.com/classes_objects/serialization.html