 

function setModifiedByModifiedOn() {

var modified_on = new Date();
            Xrm.Page.getAttribute("btsss_incomemodifiedon").setValue(modified_on );       

var setUservalue = new Array();
 setUservalue[0] = new Object();
 setUservalue[0].id = Xrm.Page.context.getUserId();
 setUservalue[0].entityType = 'systemuser';
setUservalue[0].name = Xrm.Page.context.getUserName();
 
   Xrm.Page.getAttribute("btsss_incomemodifiedby").setValue(setUservalue); 
  

        }