how to create a dynamic fileupload on clicking add and remov

Question

For example

1) A file upload control is available already

2) If the user clicks on (+) button a new fil upload control is added dynamically.

3) If the user clicls (-) button the newly added file upload control will be removed.

4) In this way if the user clicks on the upload button all the files must be uploaded together to a folder

How this is possible pls help me