This question already has an answer here:
I have this input
<form action="<?=isset($_GET['tree'])?'edit.php':'save.php'?>" method="post" enctype="multipart/form-data" id="<?=isset($_GET['tree'])?'edit-form':'csv-form'?>">
....
.....
<input type="file" name="doc" id="doc" multiple>
I'm trying to handle the uploaded files but with
var_dump($_FILES);
$_FILES only contains the last selected file.
</div>
use the name tag with square brackets: <input type="file" name="doc[]" id="doc" multiple>
Use like this.
<input type="file" id="doc" name="doc[]" multiple>