Im trying to do something similar, I want a text box populated but I want the time that it was submitted.  I have a similar bit of javascript code but that is the time which the form was loaded.  Sadly the specific users may start it and then walk away an potentially come back a half hour later so I need the time the actually hit the submit button.  Is there anyway to do this?

The only thing I  could imagine this is to run a workflow to populate that field after it was submitted.

We currently capture this information (plus UTC to keep us on the up and up with auditors). Here's an example for when the Engineering Manager clicked the approve button (emDateSigned). Hope this helps.

$(document).ready(function(){

//capture timestamp
  $('.Approve').click(timestamp);

  function timestamp() {
    
    var d = new Date();
    
    var minutes = d.getMinutes();
    var hours = d.getHours();
        
    var fullYear = d.getFullYear();
    var day = d.getDate();  //returns day as 1-31
    var month = d.getMonth() + 1;  //getMonth returns month as 0-11
    var fullDate = month + "/" + day + "/" + fullYear;
    
    var tz = new Date().getTimezoneOffset();
    var tzDiff = (tz/60);
    var utc = "(UTC-";
    if (tzDiff !== 0) {
      if (tzDiff.length = 1) {
        tzDiff = '0' + tzDiff;
        tzDiff += ':00';
      }
  	  utc += tzDiff > 0 ? '+' : '';
  	  utc += tzDiff + ")";
    }    
    
    if (minutes < 10) {var minutes = "0" + minutes;}
        
    if (d.getHours() < 12) {var a = "AM";}
	else if (d.getHours() == 12) {var a = "PM";}
	else {var a = "PM"; hours = hours - 12;}

    if ($(this).hasClass('Approve')) {
       $('.emDateSigned input').attr("readonly", false);
       $('.emDateSigned input').val(fullDate + " " + hours + ":" + minutes + " " + a + " " + utc)
       $('.emDateSigned input').attr("readonly", true);
    }
  };

});  //close document.ready