How to display both date and time as per system/local date and time format?

Hi,

I want to display a column like 'modifieddatetime' as per local/system date time format in excel sheet in vsto/c#.I can display only date in local format but not time along with the date

Is there any provision to apply any format programatically to display both date and time as per system/local date and time format.

Any help will be highly appreciated.

Thanks