$("#btn").click(function(){
$.ajax({
  do something 
});
return false;

})

function getTime(){
  var datTime = new Date();
  var sep1 = "-",sep2=":";
  
  var year = datTime.getFullYear();
  var mon = datTime.getMonth()+1;
  var day = datTime.getDate();
  var hour = datTime.getHours();
  var min = datTime.getMinutes();
  var sec = datTime.getSeconds();
  time = year + sep1 + mon + sep1 + day + " "+ hour + sep2 + min + sep2 + sec;
  $("#content1>p").text(time);
  
}