PHP Undefined index on file upload - php

Question

I'm trying to upload a file but I always get an error:
Notice: Undefined index: file_pdf in C:\xampp\htdocs\FYP2\site_admin\pentadbiran\upload.php on line 10
The example of my code get data from a form and upload to my database for the information given, such as file_reference, file_name, file_location and file_pdf.
But the problem is, the code runs well but does not update on file_pdf column in table. But the file upload into target folder is working.
if (isset($_POST['submit'])) {
$file_reference = $_POST['file_reference'];
$file_name = $_POST['file_name'];
$file_location = $_POST['file_location'];
$file_pdf = $_POST['file_pdf'];
if ($_FILES['file_pdf']['error'] == UPLOAD_ERR_OK)
{
$ext = strtolower(pathinfo($_FILES['file_pdf']['name'],PATHINFO_EXTENSION));
switch ($ext)
{
case'pdf':
break;
default:
throw new InvalidFileTypeException($ext);
}
$targetfolder = "pdf/";
$targetfolder = $targetfolder . basename($_FILES['file_pdf']['name']);
if (move_uploaded_file($_FILES['file_pdf']['tmp_name'], $targetfolder)) {
echo "The file " . basename($_FILES['file_pdf']['name']) . " is uploaded";
} else {
echo "Problem uploading file";
}
$sql = "INSERT INTO file (file_reference,file_name,file_location,file_pdf)
VALUES ('$file_reference','$file_name','$file_location','$file_pdf')";
if ($conn->query($sql) === TRUE) {
echo "New record created successfully";
} else {
echo "Error: " . $sql . "<br>" . $conn->error;
}
}
The code is run but on my database the file_pdf does not update.Why is this?

Answer 1

The global $_FILES will contain all the uploaded file information. Its contents from the example form is as follows. Note that this assumes the use of the file upload name userfile, as used in the example script above. This can be any name.
$_FILES['userfile']['name'] The original name of the file on the client machine.
$_FILES['userfile']['type'] The mime type of the file, if the browser provided this information. An example would be "image/gif". This mime type is however not checked on the PHP side and therefore don't take its value for granted.
$_FILES['userfile']['size'] The size, in bytes, of the uploaded file.
$_FILES['userfile']['tmp_name'] The temporary filename of the file in which the uploaded file was stored on the server.
$_FILES['userfile']['error'] The error code associated with this file upload.
Change this...
$file_pdf = $_POST['file_pdf'];
to
$file_pdf = $_FILES['file_pdf']['name'];