I think you want to store only the date or time, right?
Anyway, to store the current time to a string variable, you can use this code:
DateTime dt = DateTime.Now;
string time = dt.ToShortTimeString();
And you can simple print the output (If you're using console application)
Console.WriteLine(time);
And you can store the date by using this:
DateTime dt = DateTime.Now;
string date = dt.ToShortDateString();
And you can simple print it like the time variable.
What we have done is that we have stored in the string variable the time or date in the string format. Simple enough?