How to change a file input's FileList programmatically?

Issue

I have this input of type "file", and I want to change its files list. Example:

<input type = "file" id = "fileinput" />
<script type = "text/javascript">
  document.getElementById("fileinput").files = [10];
</script>

The problem is that the fileinput element's files list is not set. How do I do it?

Solution

For security reasons, browsers prevent javascript from changing the files which will be uploaded: only the user can select files via the user interface. This is to prevent an evil script to upload /etc/passwd, for example, without the user knowing.

The one exception is that calling "reset" on the form will clear the file or filelist, but you can never add to programmatically.

Answered By - odrm