Вон тебе minimal-demo:
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Demo</title>
</head>
<body>
<form>
Enter file id:<br>
<input type="text" id="id" required><br><br>
Select file:<br>
<input type="file" id="file" accept="application/pdf" required><br><br>
<input type="submit" value="Upload">
</form>
<script src="https://code.jquery.com/jquery-3.4.1.min.js"></script>
<script>
(function() {
$('form').submit(function(e) {
e.preventDefault();
var formData = new FormData();
formData.append('file', document.getElementById('file').files[0]);
formData.append('id', document.getElementById('id').value);
$.ajax({
url: 'upload.php',
data: formData,
processData: false,
contentType: false,
type: 'POST',
success: function(res) {
console.log(res)
}
});
});
})();
</script>
</body>
</html>
upload.php<?php
var_dump($_REQUEST);
var_dump($_FILES);
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