User uploading images to specific directories

So basically I have a site in which certain members are allowed to upload images (comic pages) to their own image galleries (to a specific comic). I have a successful image uploading script that I used to upload profile/avatar images for each member, but now that I want to upload files to a more specific place I'm having a little trouble.

Here's what I have so far:

(This is what appears at the top of the page)

<?php
session_start();
$toplinks = "";
if (isset($_SESSION['id'])) {
    // Put stored session variables into local php variable
    $userid = $_SESSION['id'];
    $username = $_SESSION['username'];
    $toplinks = '<a href="member_profile.php?id=' . $userid . '">' . $username . '</a> &bull; 
    <a href="member_account.php">Account</a> &bull; 
    <a href="logout.php">Log Out</a>';
} else {
    $toplinks = '<a href="join_form.php">Register</a> &bull; <a href="login.php">Login</a>';
}
?>

(This is the uploading script)

<?php
// Here we run a login check
if (!isset($_SESSION['id'])) { 
   echo 'Please <a href="login.php">log in</a> to access your account';
  exit(); 
} 
// Place Session variable 'id' into local variable
$id = $_SESSION['id'];
// Process the form if it is submitted
if ($_FILES['uploadedfile']['tmp_name'] != "") {
    // Run error handling on the file
    // Set Max file size limit to somewhere around 120kb
    $maxfilesize = 400000;
    // Check file size, if too large exit and tell them why
    if($_FILES['uploadedfile']['size'] > $maxfilesize ) { 
        echo "<br /><br />Your image was too large. Must be 400kb or less, please<br /><br />
        <a href=\"upload_comic.php\">click here</a> to try again";
        unlink($_FILES['uploadedfile']['tmp_name']); 
        exit();
    // Check file extension to see if it is .jpg or .gif, if not exit and tell them why
    } else if (!preg_match("/\.(gif|jpg|png)$/i", $_FILES['uploadedfile']['name'] ) ) {
        echo "<br /><br />Your image was not .gif, .jpg, or .png and it must be one of those three formats.<br 开发者_如何学Python/>
        <a href=\"upload_comic.php\">click here</a> to try again";
        unlink($_FILES['uploadedfile']['tmp_name']);
        exit();
        // If no errors on the file process it and upload to server 
    } else { 
        // Rename the pic
        $newname = ""; //numbers only, so they show up sequentially
        // Set the direntory for where to upload it, use the member id to hit their folder 
        // Upload the file
        if (move_uploaded_file($_FILES['uploadedfile']['tmp_name'], "comics/$comicid/".$newname)) {
            echo "Success, the image has been uploaded and will display to visitors!<br /><br />
            <a href=\"member_account.php\">Click here</a> to return to your profile edit area";
            exit();
        } else {
            echo "There was an error uploading the file, please try again. If it continually fails, contact us by email. <br /><br />
            <a href=\"member_account.php\">Click here</a> to return to your profile edit area";
            exit();
        }
    } // close else after file error checks
} // close if post the form
?>

Ideally, I would like to be able to upload an image like this: comics/comic_id/chapter_id/uploaded_file.extension

With the user profile image uploader, I was able to grab the $ID from the $_Session['id'] variable, but with the comics, I don't really know how to grab that information and use it to set the comic_id directory (chapter_id will be selected on the form so I'm not too worried about that one).

Any thoughts?

You can upload a file to wherever you choose. This will save the comic in a folder of its id and chapter, but retaining the filename. If you wanted to use the comic id as the filename I am sure you can work that out.

$basepath = "/home/path/to/www/comics/member_" . $member_id . "/";

function construct_path($chapter_id,$comic_id) 
{
   $saveimagepath = $basepath . $comic_id . $chapter
}

if (!isset($_SESSION['id'])) { 
   echo 'Please <a href="login.php">log in</a> to access your account';
  exit(); 
} 
// Place Session variable 'id' into local variable
$id = $_SESSION['id'];
// Process the form if it is submitted
if ($_FILES['uploadedfile']['tmp_name'] != "") {
    // Run error handling on the file
    // Set Max file size limit to somewhere around 120kb
    $maxfilesize = 400000;
    // Check file size, if too large exit and tell them why
    if($_FILES['uploadedfile']['size'] > $maxfilesize ) { 
        echo "<br /><br />Your image was too large. Must be 400kb or less, please<br /><br />
        <a href=\"upload_comic.php\">click here</a> to try again";
        unlink($_FILES['uploadedfile']['tmp_name']); 
        exit();
    // Check file extension to see if it is .jpg or .gif, if not exit and tell them why
    } else if (!preg_match("/\.(gif|jpg|png)$/i", $_FILES['uploadedfile']['name'] ) ) {
        echo "<br /><br />Your image was not .gif, .jpg, or .png and it must be one of those three formats.<br />
        <a href=\"upload_comic.php\">click here</a> to try again";
        unlink($_FILES['uploadedfile']['tmp_name']);
        exit();
        // If no errors on the file process it and upload to server 
    } else { 
        // Rename the pic
        $newname = $saveimagepath . $_FILES['uploadedfile']['tmp_name']; 
//numbers only, so they show up sequentially
        // Set the direntory for where to upload it, use the member id to hit their folder 
        // Upload the file
        if (move_uploaded_file($_FILES['uploadedfile']['tmp_name'], $newname)) {
            echo "Success, the image has been uploaded and will display to visitors!<br /><br />
            <a href=\"member_account.php\">Click here</a> to return to your profile edit area";
            exit();
        } else {
            echo "There was an error uploading the file, please try again. If it continually fails, contact us by email. <br /><br />
            <a href=\"member_account.php\">Click here</a> to return to your profile edit area";
            exit();
        }
    } // close else after file error checks
} // close if post the form
?>

The $_SESSION variable is available at any site you started with session_start(). So if the id is set right after the login, you can access this value at any other page in the same way with $_SESSION['id']. Make sure that the value of id won't kill your filesystem or leads to security issues!