How to Validate Date in a SharePoint 2013 List

Got the chance to work on validation on list and list forms customization on SharePoint 2013 online.

Hide or show list form fields in SharePoint using jQuery

David Lozzi has written a jquery library which is useful our daily development activites.
http://davidlozzi.com/2014/01/14/sharepoint-2013-script-hide-or-disable-your-fields
ExecuteOrDelayUntilScriptLoaded(function(){

  Lozzi.Fields.disableWithAllowance("Employee Name",["LeaveEntryAuthorization"]);

  },"sp.js");

sp.js should load before execute the code.