[SalesForce] Date/Time field – Local and GMT

Date is timezone non-aware, in fact, so is datetime (its stored at the server as GMT and re-rendered based on users TZ).
Unless you hard-code a base time for your date in Apex code/Trigger, your going to want store a datetime value instead of a date. If you dont want the time part to show up, look into creating a formula field that renders the date based upon the (hidden) datetime field. That should maintain the correct date rendered for their timezone.

Well I came across this problem and this gets uglier when you are converting the double value returned from apex into date, the timezone offset gets added into the time and can even change the date!!!.

Well to fix this I wrote a simple js function which nulifies the effect by subtracting the offset back from the date.

function normalizeDate(mydate){
   mydate = new Date(mydate );
   mydate = new Date(mydate - mydate.getTimezoneOffset() * 60000);
   return mydate;
 }

You can use the above function and try doing something like this :

 //obj is record returned by js remoting 
    obj.Custom_Date__c = normalizeDate(obj.Custom_Date__c);

You can even extend the above js function to print a date string

function normalizeDateExtended(mydate){
    mydate = new Date(mydate);
    data = new Date(mydate -  mydate.getTimezoneOffset() * 60000);
    var d = mydate.getDate();
    var m = mydate.getMonth()+1;
    var y = mydate.getFullYear();
    return ''+ (m<=9?'0'+m:m) +'-' + (d<=9?'0'+d:d)+'-' + y;
}