DateTime.TryParseExact won't parse what appears to be a valid date string

Question

This is going to be one of those "I can't believe I didn't think of that" questions, but it's been vexing me for going on two days.

I've got bunch of date strings (and many more columns of data) coming out of a .csv file that are in this format: 8/8/2017 8:57

I've read through the SO questions here and here as well as the documentation on MSDN from here and here .

Here are a couple of things I've tried in C# statements in LINQPad, adapted from the MSDN examples :

string[] data = { "8/8/2017 8:57,-1.220135,-1.239456,-3.20E-08,-4.47E-09,-1.202865"};
Console.WriteLine(data);

string dateValue = "8/8/2017 8:57";
string[] patterns = {"M/d/yyyy H:mm", "MM/dd/yyyy H:mm"};

DateTime parsedDate;

if (DateTime.TryParseExact(data[0].ToString(), patterns,
       System.Globalization.CultureInfo.CurrentCulture,
       System.Globalization.DateTimeStyles.None,
       out parsedDate))
{
    Console.WriteLine("Converted '{0}' to {1}.",
    dateValue,
    parsedDate);
}
else
{
    Console.WriteLine("Unable to convert '{0}' to a date and time.",
    dateValue);
}

if (DateTime.TryParseExact(data[0].ToString(),
    patterns,
    null,
    System.Globalization.DateTimeStyles.None,
    out parsedDate))
{
    Console.WriteLine("Converted '{0}' to {1}.",
    dateValue, 
    parsedDate);
}
else
{
    Console.WriteLine("Unable to convert '{0}' to a date and time.",
    dateValue);
}

Both result in:

Unable to convert '8/8/2017 8:57' to a date and time.

Unable to convert '8/8/2017 8:57' to a date and time.

I've tried several variants in the string[] patterns... declaration to no avail.

What am I missing? I suspect the problem lies in my patterns array, but maybe not? This seems like it should be easy.

I'm not married to DateTime.TryParseExact() , so long as I get a valid DateTime out of the conversion.

Edit: After some of the comments, I've checked my CultureInfo.CurrentCulture , and it is en-US , which should be fine, or at least I think so.

Edit1: As pointed out by most, I was using an entire string instead of the date value, although I still get an error using the single string. Here's the first if() modified as suggested by Joel below:

string[] data = "8/8/2017 8:57,-1.220135,-1.239456,-3.20E-08,-4.47E-09,".Split(',');
string dateValue = "8/8/2017 8:57";
string[] patterns = {"M/d/yyyy H:mm"};

DateTime parsedDate;

if (DateTime.TryParseExact(data[0], patterns,
       System.Globalization.CultureInfo.CurrentCulture,
       System.Globalization.DateTimeStyles.None,
       out parsedDate))
{
    Console.WriteLine("Converted '{0}' to {1}.",
    dateValue,
    parsedDate);
}
else
{
    Console.WriteLine("Unable to convert '{0}' to a date and time.",
    dateValue);
}

I've managed to incorporate a version of this into my production code that's working as expected. Thanks for the help.

Answer 1

Look carefully at your data:

string[] data = { "8/8/2017 8:57,-1.220135,-1.239456,-3.20E-08,-4.47E-09,-1.202865"};

This array has only one element, where the value of that element is all of the text. It seems different in the console messages because you put the 8/8/2017 8:57 value into a separate variable, rather than using the array.

Did you perhaps want this instead?

string[] data={"8/8/2017 8:57","-1.22013","-1.239456","-3.20E-08","-4.47E-09","-1.202865"};

Or maybe you wanted this:

var data = "8/8/2017 8:57,-1.220135,-1.239456,-3.20E-08,-4.47E-09,-1.202865".Split(',');

^{**Note I don't generally condone using .Split() as a csv parser, but for this simple example it gets the point across.}

Whatever you do, I'd make sure your Console messages accurately reflect what you tried to do (use data[0] as the first substitution), so you can be sure the TryParseExact() method is looking at the string you think it is.