// handle on Enter key events
var onEnterExecute = ""; 
try 
{
  document.addEventListener("keypress", Key, true);
} 
catch(e){
  try 
  {
    document.attachEvent("onkeypress", Key);
  } 
  catch(e)
  {
    alert(e);
  }
}

function Key(e)
{
  try 
  {
    var key = window.event.keyCode;
  } 
  catch(ex)
  {
    var key = e.which;
  }
		  
  if(key == 13)
  {
    eval(onEnterExecute);
    return false;
  }
}