function check()
{
var filedesc=document.getElementById('filedesc')
var filename=document.getElementById('filename')
var ext = filename.value;
ext = ext.substring(ext.length-3,ext.length);
ext = ext.toLowerCase();

var c=0
if(ext == '')
{
alert("Please Specify a file to upload")
c=1
}
if(ext !='')
{
if(ext != 'pdf') {
    alert('You selected a .'+ext+ 
          ' file; please select a .pdf file instead!');
  c=1
  }
}
if(filename.FileUpload=="")
{
alert('File Upload Cannot be Blank')
c=1
}
if(filedesc.value=="")
{
alert('File Description Cannot be Blank')
c=1
}
if(c==0)
{
  window.document.form1.action='create_feedback';
  window.form1.submit();
}
}