現在、ユーザーが投稿した広告を編集できる PHP 編集スクリプトが動作していますが、ユーザーが?id=番号を変更して別のデータ セットを表示し、他の人のデータを編集してデータベースに保存できることに気付きました。
ユーザーが投稿した広告をクリックして編集するときに、アクセスできるのは自分の広告だけであり、id を調整して他の人の広告を編集できないようにする方法はありますか?=フォームを操作から保護する方法は？
これが私の現在のコードです：
<?php
/*
EDIT.PHP
Allows user to edit specific entry in database
*/
// creates the edit record form
// since this form is used multiple times in this file, I have made it a function that is easily reusable
function renderForm($id, $fname, $lname, $contact, $price, $error)
{
?>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<title>Edit Record</title>
<link rel="stylesheet" type="text/css" href="stylesheet.css">
<style type="text/css">
#page-wrap {
position:absolute;
top: 206px;
left: 288px;
width: 50%;
text-align:left;
background-color:#FFF;
padding: 10px;
border-radius: 10px;
box-shadow: 1px 2px 2px #888888;
}
</style>
<script type = "text/javascript">
function myfunction(url)
{
window.location.href = url;
}
</script>
</head>
<body>
<div class="container">
<div id="imagelogo" onclick = "window.location.href = 'index.html'" >
<p> Buy and sell stuff around University</p>
</div>
<ul id="navigation" name="navigation">
<li id="nav-home"><a href="index.html">Home</a></li>
<li id="nav-search"><a href="search.php">Search</a></li>
<li id="nav-selling"><a href="#">Selling</a></li>
<li id="nav-buying"><a href="#">Buying</a></li>
<li id="nav-FAQ"><a href="#">FAQ</a></li>
<li id="nav-contact"><a href="#">Contact</a></li>
<p> </p>
<p> </p>
<p> </p>
<p>Sponsors</p>
</ul>
<div id="account">
<?php
if( isset( $_SESSION['username'] ) ){
echo "<a href='securedpage1.php'>My Account</a><img src='images/uni-icon.png' width='30' height='18' style='vertical-align: middle;'/>";
}else{
echo "<a href='login.php' >Login</a><img src='images/uni-icon.png' width='30' height='18' style='vertical-align: middle;'/>";
}
?>
</div>
<div id="registerlogout">
<?php
if( isset( $_SESSION['username'] ) ){
echo "<a href='logout.php'>Logout</a>";
}else{
echo "<a href='register.php'> Register</a>";
}
?>
</div>
<div id="social">
<img src="images/fb-logo.png" width="22" height="20" />
<img src="images/twitter-logo.png" width="24" height="25" />
</div>
<div id="page-wrap">
<?php
// if there are any errors, display them
if ($error != '')
{
echo '<div style="padding:4px; border:1px solid red; color:red;">'.$error.'</div>';
}
?>
<form action="" method="post">
<input type="hidden" name="id" value="<?php echo $id; ?>"/>
<div>
<strong>Ad Title: *</strong> <input type="text" name="fname" style="width: 60%; box- sizing: border-box; -moz-box-sizing: border-box; -webkit-box-sizing: border-box;"value="<?php echo $fname; ?>"/><br/>
<strong>Description: *</strong> <textarea name="lname" cols="45" rows="5"><?php echo $lname; ?></textarea><br/>
<strong>Contact*</strong> <input type="text" name="contact" style="width: 60%; box- sizing: border-box; -moz-box-sizing: border-box; -webkit-box-sizing: border-box;" value="<?php echo $contact; ?>"/><br/>
<strong>Price*</strong> <input type="text" name="price" style="width: 60%; box-sizing: border-box; -moz-box-sizing: border-box; -webkit-box-sizing: border-box;" value="<?php echo $price; ?>"/><br/>
<p>* Required</p>
<input type="submit" name="submit" value="Submit">
</div>
</form>
</div>
</div>
</body>
</html>
<?php
}
// Inialize session
session_start();
// connect to the database
include('conn.php');
// check if the form has been submitted. If it has, process the form and save it to the database
if (isset($_POST['submit']))
{
// confirm that the 'id' value is a valid integer before getting the form data
if (is_numeric($_POST['id']))
{
// get form data, making sure it is valid
$id = $_POST['id'];
$fname = mysql_real_escape_string(htmlspecialchars($_POST['fname']));
$lname = mysql_real_escape_string(htmlspecialchars($_POST['lname']));
$contact = mysql_real_escape_string(htmlspecialchars($_POST['contact']));
$price = mysql_real_escape_string(htmlspecialchars($_POST['price']));
// check that firstname/lastname fields are both filled in
if ($fname == '' || $lname == '' || $contact == '' || $price == '' )
{
// generate error message
$error = 'ERROR: Please fill in all required fields!';
//error, display form
renderForm($id, $fname, $lname, $contact, $price, $error);
}
else
{
// save the data to the database
mysql_query("UPDATE people SET price='$price', contact='$contact', fname='$fname', lname='$lname' WHERE id='$id'")
or die(mysql_error());
// once saved, redirect back to the view page
header("Location: view.php");
}
}
else
{
// if the 'id' isn't valid, display an error
echo 'Error!';
}
}
else
// if the form hasn't been submitted, get the data from the db and display the form
{
// get the 'id' value from the URL (if it exists), making sure that it is valid (checing that it is numeric/larger than 0)
if (isset($_GET['id']) && is_numeric($_GET['id']) && $_GET['id'] > 0)
{
// query db
$id = $_GET['id'];
$result = mysql_query("SELECT * FROM people WHERE id=$id")
or die(mysql_error());
$row = mysql_fetch_array($result);
// check that the 'id' matches up with a row in the databse
if($row)
{
// get data from db
$fname = $row['fname'];
$lname = $row['lname'];
$contact = $row['contact'];
$price = $row['price'];
// show form
renderForm($id, $fname, $lname, $contact, $price, '');
}
else
// if no match, display result
{
echo "No results!";
}
}
else
// if the 'id' in the URL isn't valid, or if there is no 'id' value, display an error
{
echo 'Error!';
}
}
?>