1. Get total hours between two datetime
.ForMember(desc => desc.TotalDowntime, opt => opt.MapFrom(src => src.BeginTimestamp.Value.Subtract((DateTime)src.ErrorResolvedTimestamp).Hours))
2. Datetime to string
.ForMember(desc => desc.BeginDate, opt => opt.MapFrom(src => src.BeginTimestamp.Value.ToString("dd/MM/yyyy", CultureInfo.InvariantCulture)))
.ForMember(desc => desc.ErrorOccurrenceTime, opt => opt.MapFrom(src => src.BeginTimestamp.Value.ToString("hh:mm:ss", CultureInfo.InvariantCulture)));
3. String to Datetime
.ForMember(desc => desc.ErrorDateTime, opt => opt.MapFrom(src => srcDateTime.ParseExact("24/01/2013", "dd/MM/yyyy", CultureInfo.InvariantCulture)));