function startFileUpload(){
      document.getElementById('f1_upload_process').style.visibility = 'visible';
      document.getElementById('f1_upload_form').style.visibility = 'hidden';
      return true;
}

function stopFileUpload(value){
      var result = '';
			
			if (value == 1){
         result = '<span class="msg">file succesvol toegevoegd!<\/span><br/><br/>';
      }
			if (value == 2){
         result = '<span class="msg">_$FILES error<\/span><br/><br/>';
      }
			if (value == 3){
         result = '<span class="msg">file reeds aanwezig<\/span><br/><br/>';
      }
			if (value == 4){
         result = '<span class="msg">file groter dan 100 MB<\/span><br/><br/>';
      }
			if (value == 5){
         result = '<span class="msg">alleen zip files toegestaan<\/span><br/><br/>';
      }
  						
			document.getElementById('f1_upload_form').style.visibility = 'visible';
			document.getElementById('okbutton').style.visibility = 'visible'; 
      document.getElementById('f1_upload_process').style.visibility = 'hidden';
      document.getElementById('f1_upload_result').innerHTML = result;     
      return true;   
}