shield Enter key in pages

<script type="text/javascript">

window.document.onkeydown = function()

{

         if((document.activeElement.type!='button')

         && (document.activeElement.type!='submit')

        && (event.keyCode==13))

        {

              if(document.activeElement.type=='textarea')

              {

              }

        }

    else

    {

         event.returnValue = false;

     }

   }

}

</script>

Reference : http://blog.csdn.net/wang8712/archive/2008/04/18/2303340.aspx