[eluser]manisha[/eluser]
It get resolved.... It was the place of <form> tag which was causing the problem as my form was containing other fields as well( embedded in table structure ) along with file input field .... So I placed <form action="upload/do_upload" method="post" enctype="multipart/form-data"> tag immediately after <body> tag...
So now I am getting values in $_FILES when I submit the form....
Thanks...