Converting string to valid DateTime

Question

I know there are allot of questions regarding this, but I've been trying all day to get this conversion to work and have had no luck when applying the answers to the same question posted here. Every time I try to Parse the string to a DateTime, I get a "String was not recognized as a valid DateTime" exception. If I use Convert.ToDateTime, I can get a Date back from my string, but I need the hh:ss as well.

Here is my simplified code that is ruining my day:

var test = "2015-05-08T05:00Z";

DateTime testTime = new DateTime();
//testTime = Convert.ToDateTime(test);
testTime = DateTime.ParseExact(test, "mm/DD/yyyy HH:ss",
System.Globalization.CultureInfo.InvariantCulture);

Console.WriteLine(testTime);

Why is this string not recognized as a valid DateTime when trying to convert? All help is appreciated

Answer 1

Try this...

var test = "2015-05-08T05:00Z";
DateTime testTime = new DateTime();
testTime = DateTime.Parse(test, null, System.Globalization.DateTimeStyles.RoundtripKind);

Console.WriteLine(testTime);
Console.ReadLine();

Or even with DateTime.ParseExact()

var test = "2015-05-08T05:00Z";

DateTime testTime = new DateTime();
testTime = DateTime.ParseExact(test, "yyyy-MM-ddTHH:ssZ", System.Globalization.CultureInfo.InvariantCulture, DateTimeStyles.RoundtripKind);

Console.WriteLine(testTime);
Console.ReadLine();

Results:

Answer 2

You are doing an exact parse, which means that the parse format string must match exactly with your date literal string. But your parse format string in ParseExact

1. uses / instead of - in the test literal string.
2. has a space instead of the T in the test literal string
3. does not match Z at the end of your test literal string.
4. Further it is not in yyyy-MM-dd order of your test literal string.

@Shar1er80' s solution is nice and frees you from having to specify a correct parse format string for ParseExact. I'd recommend going with that.

However, if you want to use ParseExact, you need to do this:

testTime = DateTime.ParseExact(test, "yyyy-MM-ddTHH:ssZ",
    System.Globalization.CultureInfo.InvariantCulture, System.Globalization.DateTimeStyles.AdjustToUniversal);

Note that I added a DateTimeStyle of AdjustToUniversal to ensure that your time is interpreted as UTC. The Z in the parse format string is just there to consume a Z. See https://stackoverflow.com/a/833143/49251 for more info on the issue of Z not actually being a part of the format string per se.

Answer 3

The format string you are using ("mm/DD/yyyy HH:ss") doesn't match your input in any way.

Have you looked at the DateTime.ParseExact documentation? You could try something like this:

testTime = DateTime.ParseExact(test, "yyyy-MM-ddTHH:ssZ", 
    System.Globalization.CultureInfo.InvariantCulture, 
    System.Globalization.DateTimeStyles.AssumeUniversal);

A couple of notes:

1. There is no point in setting testTime = new DateTime() if you are going to parse it on the next line. Just drop that line entirely and use var testTime = DateTime.ParseExact(...);
2. Are you sure that HH:ss is what you want? That seems like a very strange way to write a time. HH:mm or mm:ss would make more sense.

Answer 4

You should fix your expected pattern and take the time zone into account.

If your need a DateTime of DateTimeKind.Local:

var date = DateTime.ParseExact("2015-05-08T05:00Z", "yyyy-MM-dd'T'HH:mm'Z'",
   CultureInfo.InvariantCulture);

If your need a DateTime of DateTimeKind.Utc:

var date = DateTime.ParseExact("2015-05-08T05:00Z", "yyyy-MM-dd'T'HH:mm'Z'",
   CultureInfo.InvariantCulture,
    DateTimeStyles.AssumeUniversal 
  | DateTimeStyles.AdjustToUniversal);