Comments by Mukesh.Ce62 (Top 5 by date)

You have to store datetime in database after then get date in backend and store in datetime object.

DateTime dtStart = DateTime.Now.Date; // here your date

then you can compare with other data like below
DateTime dtend = DateTime.Now.Date;
DateTime final = Convert.ToDateTime(dtend.Date - dtStart.Date);

And in last you can give format to your compared date.
string time = final.ToString("HH:MM");

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