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POphp variable gets null at the end of the script?
 

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  1. POphp variable gets null at the end of the script?
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    <p>I have a problem that I really can't figure out. basically I'm working on a blog and I have a variable from a cookie that returns a post id. the problem is that at the end of the script, when I enter an if(isset) statement, the variable seems to be null and I can't understand the reason behind it. it won't add anything to the database and it won't redirect to the post id. here's the script:</p> <pre><code>&lt;?php //display the post $post_id = $_GET['post_id']; $query = mysql_query("SELECT * FROM posts WHERE `post_id`='". $post_id. "';") or die(mysql_error()); if(mysql_num_rows($query) != 0) { $currentrow = mysql_fetch_array($query); echo $currentrow['title']. "&lt;br&gt;". $currentrow['text']; } else { echo "that post does not exist."; } ?&gt; &lt;/div&gt; &lt;div id="comments"&gt; &lt;br&gt; &lt;h3&gt;Comments&lt;/h3&gt; &lt;br&gt; &lt;?php //display the comments $comments = mysql_query("SELECT * FROM `comments` JOIN `posts` ON(posts.post_id=comments.post_id) JOIN `users` ON(users.user_id=comments.user_id) WHERE posts.post_id=". "'". $_GET['post_id']. "'". ";")or die(mysql_error());; while($currentRow = mysql_fetch_array($comments)) { echo $currentRow['ctext']. "&lt;br&gt;"; echo "posted by &lt;a href='/templates/profile.php?name=". $currentRow['name']. "'&gt;". $currentRow['name']. "&lt;/a&gt; at ". $currentRow['cdate']. " -- ". $currentRow['ctime']. "&lt;br&gt;&lt;br&gt;"; } ?&gt; &lt;/div&gt; &lt;Form Name ="submitform" Method ="POST" ACTION = "post.php"&gt; &lt;div id="commentbox"&gt; &lt;textarea name="textarea1" rows="10" cols="30"&gt; &lt;?php echo $post_id; ?&gt; &lt;/textarea&gt; &lt;br&gt; &lt;input type="submit" name="submitcomment" value="Submit"&gt;&lt;br&gt; &lt;/div&gt; &lt;/Form&gt; &lt;?php if(isset($_POST['submitcomment'])) { $comment = $_POST['textarea1']; $user_id = $_COOKIE['userid']; mysql_query("INSERT INTO comments(`ctext`, `cdate`, `ctime`, `user_id`, `post_id`) VALUES('$comment', 'CURDATE()', 'CURTIME()', '$user_id', '$post_id')") or die(mysql_error()); header('Location: /post.php?post_id='. $post_id); } ?&gt; &lt;/body&gt; &lt;/html&gt; </code></pre> <p>as you can see, I'm echoing that variable in the textarea1 just before the if statement and it returns the correct value, but at the end it's null. thanks in advance. </p>
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    1. USicarus
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    1. COLook up **SQL injection**: you have a **serious security issue** with the INSERT part. Using `$_POST['textarea1'];` without at least sanitizing with mysql_real_escape is dangerous! Google for Little Bobby Tables to see what I mean... On a second thought the SELECT is troublesome too. Not to mention: mysql_* is deprecated. Either mysqli, or better: PDO would be good.
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      1. USppeterka
    2. COwhere are you setting the COOKIE value..?
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      1. USSudhir Bastakoti
    3. COI know I have security issues, I will fix them in the last part.
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      1. USicarus
 

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