User uploading images to specific directories - php

Question

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 = '' . $username . ' •
Account •
Log Out';
} else {
$toplinks = 'Register • Login';
}
?>
(This is the uploading script)
<?php
// Here we run a login check
if (!isset($_SESSION['id'])) {
echo 'Please log in 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'] > $maxfilesize ) {
echo "<br /><br />Your image was too large. Must be 400kb or less, please<br /><br />
click here to try again";
unlink($_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", $_FILES['uploadedfile']['name'] ) ) {
echo "<br /><br />Your image was not .gif, .jpg, or .png and it must be one of those three formats.<br />
click here to try again";
unlink($_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 />
Click here 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 />
Click here 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?

Answer 1

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 log in 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'] > $maxfilesize ) {
echo "<br /><br />Your image was too large. Must be 400kb or less, please<br /><br />
click here to try again";
unlink($_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", $_FILES['uploadedfile']['name'] ) ) {
echo "<br /><br />Your image was not .gif, .jpg, or .png and it must be one of those three formats.<br />
click here to try again";
unlink($_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 />
Click here 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 />
Click here to return to your profile edit area";
exit();
}
} // close else after file error checks
} // close if post the form
?>

Answer 2

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!