Building Browsergames: Swapping Weapons (PHP)
It was a close race, but in the end the results of our poll on whether users should dual wield their weapons or have to toggle which one was active have been decided: users will toggle which weapon is currently active. Today, we’re going to be implementing that functionality.
The ’swap weapon’ page is a fairly simple one – all we need is a template and some code to handle it(we even wrote most of it earlier, when we built our weapons shop). We’ll start off with the template, and call it equipment.tpl:
<html>
<head>
<title>Equipment Management</title>
</head>
<body>
<h3>Current Equipment:</h3>
<p><a href='index.php'>Back to main</a></p>
<ul>
<li>
Primary Hand:
{if $phand ne ''}
{$phand}
<form action='weapon-shop.php' method='post'>
<input type='hidden' name='sell' value='phand' />
<input type='submit' value='Sell' />
</form>
{else}
None
{/if}
</li>
<li>
Secondary Hand:
{if $shand ne ''}
{$shand}
<form action='weapon-shop.php' method='post'>
<input type='hidden' name='sell' value='shand' />
<input type='submit' value='Sell' />
</form>
{else}
None
{/if}
</li>
</ul>
<p>
<form action='equipment.php' method='post'>
<input type='submit' value='Swap' name='swap' />
</form>
</p>
</body>
</html>
This template is relatively simple, and essentially just the top parts of the weapon shop’s template – we even left in the ‘Sell’ buttons, so that users can sell their equipment straight from their equipment page. We have to make sure that the ’swap’ button has a ‘name’ attribute – that way we can check $_POST later to see if it was clicked. Next we’ll build equipment.php, which is responsible for retrieving the current weapons a user is using, and displaying this template:
<?php
require_once 'smarty.php';
session_start();
require_once 'config.php'; // our database settings
$conn = mysql_connect($dbhost,$dbuser,$dbpass)
or die('Error connecting to mysql');
mysql_select_db($dbname);
// retrieve player's ID
$query = sprintf("SELECT id FROM users WHERE UPPER(username) = UPPER('%s')",
mysql_real_escape_string($_SESSION['username']));
$result = mysql_query($query);
list($userID) = mysql_fetch_row($result);
require_once 'stats.php'; // player stats
$phand = getStat('phand',$userID);
$shand = getStat('shand',$userID);
$phand_query = sprintf("SELECT name FROM items WHERE id = %s",
mysql_real_escape_string($phand));
$result = mysql_query($phand_query);
if($result) {
list($phand_name) = mysql_fetch_row($result);
$smarty->assign('phand',$phand_name);
}
$shand_query = sprintf("SELECT name FROM items WHERE id = %s",
mysql_real_escape_string($shand));
$result = mysql_query($shand_query);
if($result) {
list($shand_name) = mysql_fetch_row($result);
$smarty->assign('shand',$shand_name);
}
$smarty->display('equipment.tpl');
?>
Essentially, all that we’re going to be adding on to this code is handling for a POST request; if something is POSTed to this page, we swap the user’s current weapons. The code is fairly simple, as you can see:
if($_POST) {
setStat('phand',$userID,$shand);
setStat('shand',$userID,$phand);
$temp = $shand;
$shand = $phand;
$phand = $temp;
}
And that’s all there is to it! We just add another link to our index page:
<p><a href='equipment.php'>Equipment Management</a></p>
And we’re finished! Here’s the code for our template:
<html>
<head>
<title>Equipment Management</title>
</head>
<body>
<h3>Current Equipment:</h3>
<p><a href='index.php'>Back to main</a></p>
<ul>
<li>
Primary Hand:
{if $phand ne ''}
{$phand}
<form action='weapon-shop.php' method='post'>
<input type='hidden' name='sell' value='phand' />
<input type='submit' value='Sell' />
</form>
{else}
None
{/if}
</li>
<li>
Secondary Hand:
{if $shand ne ''}
{$shand}
<form action='weapon-shop.php' method='post'>
<input type='hidden' name='sell' value='shand' />
<input type='submit' value='Sell' />
</form>
{else}
None
{/if}
</li>
</ul>
<p>
<form action='equipment.php' method='post'>
<input type='submit' value='Swap' name='swap' />
</form>
</p>
</body>
</html>
And here’s the code for the file that handles the functionality behind the template:
<?php
require_once 'smarty.php';
session_start();
require_once 'config.php'; // our database settings
$conn = mysql_connect($dbhost,$dbuser,$dbpass)
or die('Error connecting to mysql');
mysql_select_db($dbname);
// retrieve player's ID
$query = sprintf("SELECT id FROM users WHERE UPPER(username) = UPPER('%s')",
mysql_real_escape_string($_SESSION['username']));
$result = mysql_query($query);
list($userID) = mysql_fetch_row($result);
require_once 'stats.php'; // player stats
$phand = getStat('phand',$userID);
$shand = getStat('shand',$userID);
if($_POST) {
setStat('phand',$userID,$shand);
setStat('shand',$userID,$phand);
$temp = $shand;
$shand = $phand;
$phand = $temp;
}
$phand_query = sprintf("SELECT name FROM items WHERE id = %s",
mysql_real_escape_string($phand));
$result = mysql_query($phand_query);
if($result) {
list($phand_name) = mysql_fetch_row($result);
$smarty->assign('phand',$phand_name);
}
$shand_query = sprintf("SELECT name FROM items WHERE id = %s",
mysql_real_escape_string($shand));
$result = mysql_query($shand_query);
if($result) {
list($shand_name) = mysql_fetch_row($result);
$smarty->assign('shand',$shand_name);
}
$smarty->display('equipment.tpl');
?>