Combine date and time when date is a DateTime and time is a string

Question

I am working with an old mysql database in which a date is stored (without a time) as a datetime and a time is stored as a string (without a date).

In C# I then have a DateTime with a value like 2010-06-25 12:00:00 AM and a String with a value like 15:02.

What is the most concise way to combine these without a lot of overhead?

I have tried a few methods including:

DateTime NewDateTime = DateTime.Parse(OldDateTime.ToString("yyyy-MM-dd ") + TimeString); 

I dislike converting the existing DateTime to a string and appending the time.

I can convert the time string to a date, but then I get today's date and adding it as a number of ticks to the old datetime is incorrect.

Note: Don't worry about validation, it is done elsewhere. The time is represented using 24-hour format without seconds.

Answer 1

You can use TimeSpan.Parse to parse the time, and then add the result to the date:

DateTime newDateTime = oldDateTime.Add(TimeSpan.Parse(timeString)); 

Answer 2

var dt = new DateTime(2010, 06, 26); // time is zero by default var tm = TimeSpan.Parse("01:16:50"); var fullDt = dt + tm; // 2010-06-26 01:16:50