Button upload issue - php

Question

I have been struggling for some time with getting this single button upload to work, i have tried several methods to submit the upload and this one i have seems to work up to the point of the php but then something in the php seems to not like the submit, without the js this works as a regular select file and upload, but soon as i add the js (which appears to work) the php then doesnt work.
Im totally confused why this is happening!
Any advice appreciated thanks!
The upload form
<form name="form" method="POST" enctype="multipart/form-data" action="updateProfilePic_script.php">
<div class="update_header_pic">
<input type = 'button' value = 'Choose image'
onclick ="javascript:document.getElementById('Photo').click();">
<input id='Photo' type='file' style='visibility: hidden;' name='Photo' onchange='submit();'/>
</div>
</form>
The php
<?
session_start();
$user = $_SESSION['username'];
$hostname = "localhost";
$db_user = "xxxusername";
$db_password = "xxxpassword";
$database = "xxxdatabase";
$db_table = "user_profile_pic"; // image table
# THIS CODE IS USED TO CONNECT TO THE MYSQL DATABASE
$db = mysql_connect($hostname, $db_user, $db_password);
mysql_select_db($database,$db);
$uploadDir = 'usermedia/users/images/profileimages/'. $user .'/';//Image Upload Folder
if (!is_dir($uploadDir) && !mkdir($uploadDir)){
die("Error creating folder $uploadDir");
}
if(isset($_POST['submit'])) {
$date = date("Y-m-d H:i:s");
$unique = substr(number_format(time() * rand(),0,'',''),0,10);
$fileName = $unique .'-'.$_FILES['Photo']['name'];
$tmpName = $_FILES['Photo']['tmp_name'];
$fileSize = $_FILES['Photo']['size'];
$fileType = $_FILES['Photo']['type'];
$filePath = $uploadDir . $fileName;
$result = move_uploaded_file($tmpName, $filePath);
if (!$result) {
echo "Error uploading file";
exit;
}
if(!get_magic_quotes_gpc())
{
$fileName = addslashes($fileName);
$filePath = addslashes($filePath);
}
$query = "INSERT INTO $db_table ( Image , username , datetime , filesize , filetype ) VALUES ('$filePath' , '$user' , '$date' , '$fileSize' , '$fileType' )";
mysql_query($query) or die('Error, query failed');
header('Location: edit_myProfile.php');
}
?>

Answer 1

In your HTML form there is no [input type=submit] then why in your PHP code you did:
if(isset($_POST['submit'])) {
//...
//..
}
You can simply change it to:
if(isset($_FILES['Photo'])) {
//the your uploading procedure
}