Get token expiration time From ArcGIS Online

Question

I am using following method to sign in to ArcGIS portal and get the token

public static IArcGISSingleSignon SingleSignon
        {
            get
            {
                if (_singleSignon == null)
                    _singleSignon = new ESRI.ArcGIS.SystemUI.ArcGISSingleSignonClass();
                return _singleSignon;
            }
        }

internal static void SignIn()
        {
            string bsToken = string.Empty, bsReferrer = string.Empty, bsUser = string.Empty;
            int IExpiration = 0;
            try
            {
                SingleSignon.GetToken(0, ref bsToken, ref bsReferrer, ref IExpiration, ref bsUser);
            }
            catch (System.Runtime.InteropServices.COMException)
            { }
        }

Documentation of the GetToken method says this about the IExpiration

lExpiration is a parameter of type long

So how do I know from this long value when my token is going to expire?

Answer 1

The value returned is the expiration time of the token in milliseconds since Jan. 1, 1970 (UTC). You can convert it to your local time by doing

var epoch = new DateTime(1970, 1, 1, 0, 0, 0, DateTimeKind.Utc);
return epoch.AddMilliseconds(longValue).ToLocalTime();