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Parsing non-standard string date to DateTime (ParseExact won't work)

I'm working on a C#-WPF parser that read lines from a document and creates objects with several fields, including a "Date added" field. Problem: the date is in a non-standard Spanish format, and I am not able to make DateTime.ParseExact work, as my research suggested. This is the code:
string input = dateAddedStringSPA; //domingo 2 septiembre 2012, 23:54:20
string format = "dddd dd MMMM yyy, HH:mm:ss";
CultureInfo cultureInfo = new CultureInfo("es-ES");
DateTime dateAddedSPA;
try
{
dateAddedSPA = DateTime.ParseExact(input, format, cultureInfo);
if (dateAddedSPA == DateTime.MinValue)
{
clipping.DateAdded = DateTime.Now; /*Added this conditional workaround to avoid an exception if parsing fails (and always fails). While this doesn't work every object will have the same date: current. */
}
else
{
clipping.DateAdded = dateAddedSPA;
}
}
catch (Exception)
{
throw new Exception("Error encountered while adding date.");
}
The comment that you can see by the side of input is the actual string format, which looks like that. "format" is my attempt to get DateTime to understand it, I also tried removing the comma after the year, still didn't work. I'm not sure if it's the culture the one causing the problems, but I'm afraid my expertise isn't enough yet to know. Thing is, parsing fails and I get the date set to 1/1/0001 12:00:00 AM. Any hint that what could be happening here?
Thanks in advance.

To make the solution more "universal" you can specify multiple formats and use TryParseExact() .NET/C# method as shown in the following demo sample code snippet:
CultureInfo cultureInfo = new CultureInfo("es-ES");
string[] formats ={"dddd d MMMM yyy, HH:mm:ss", "dddd d MMMM yyy, HH:mm:ss"};
string input = "domingo 2 septiembre 2012, 23:54:20";
DateTime dt;
if (DateTime.TryParseExact(input, formats, cultureInfo, DateTimeStyles.None, out dt));
{
if (dt<DateTime.Now)
Console.WriteLine("OK");
Console.ReadKey();
}
Hope this may help.

Convert string to Time

I have a time that is 16:23:01. I tried using DateTime.ParseExact, but it's not working.
Here is my code:
string Time = "16:23:01";
DateTime date = DateTime.ParseExact(Time, "hh:mm:ss tt", System.Globalization.CultureInfo.CurrentCulture);
lblClock.Text = date.ToString();
I want it to show in the label as 04:23:01 PM.

"16:23:01" doesn't match the pattern of "hh:mm:ss tt" - it doesn't have an am/pm designator, and 16 clearly isn't in a 12-hour clock. You're specifying that format in the parsing part, so you need to match the format of the existing data. You want:
DateTime dateTime = DateTime.ParseExact(time, "HH:mm:ss",
CultureInfo.InvariantCulture);
(Note the invariant culture, not the current culture - assuming your input genuinely always uses colons.)
If you want to format it to hh:mm:ss tt, then you need to put that part in the ToString call:
lblClock.Text = date.ToString("hh:mm:ss tt", CultureInfo.CurrentCulture);
Or better yet (IMO) use "whatever the long time pattern is for the culture":
lblClock.Text = date.ToString("T", CultureInfo.CurrentCulture);
Also note that hh is unusual; typically you don't want to 0-left-pad the number for numbers less than 10.
(Also consider using my Noda Time API, which has a LocalTime type - a more appropriate match for just a "time of day".)

string Time = "16:23:01";
DateTime date = DateTime.Parse(Time, System.Globalization.CultureInfo.CurrentCulture);
string t = date.ToString("HH:mm:ss tt");

This gives you the needed results:
string time = "16:23:01";
var result = Convert.ToDateTime(time);
string test = result.ToString("hh:mm:ss tt", CultureInfo.CurrentCulture);
//This gives you "04:23:01 PM" string
You could also use CultureInfo.CreateSpecificCulture("en-US") as not all cultures will display AM/PM.

The accepted solution doesn't cover edge cases.
I found the way to do this with 4KB script. Handle your input and convert a data.
Examples:
00:00:00 -> 00:00:00
12:01 -> 12:01:00
12 -> 12:00:00
25 -> 00:00:00
12:60:60 -> 12:00:00
1dg46 -> 14:06
You got the idea...
Check it https://github.com/alekspetrov/time-input-js

Check if a string is a valid date using DateTime.TryParse

I am using DateTime.TryParse() function to check if a particular string is a valid datetime not depending on any cultures.
To my surprise , the function returns true for even strings like "1-1", "1/1" .etc.
How can I solve this problem?
Update:
Does it mean, if I want to check if a particular string is valid datetime, I need a huge array of formats?? There will be different combinations , I believe.
Even there are lots of date separator ( '.' , '/' , '-', etc..) depending on the culture, it will be difficult for me to define an array of format to check against .
Basically, I want to check if a particular string contains AT LEAST day(1 through 31 or 01 through 31),month(1 through 12 or 01 through 12) and year(yyyy or yy) in any order, with any date separator , what will be the solution?
So, if the value includes any parts of time, it should return true too.
I could NOT be able to define a array of format.

If you want your dates to conform a particular format or formats then use DateTime.TryParseExact otherwise that is the default behaviour of DateTime.TryParse
DateTime.TryParse
This method tries to ignore unrecognized data, if possible, and
fills in missing month, day, and year information with the current
date. If s contains only a date and no time, this method assumes the
time is 12:00 midnight. If s includes a date component with a
two-digit year, it is converted to a year in the current culture's
current calendar based on the value of the Calendar.TwoDigitYearMax
property. Any leading, inner, or trailing white space character in s
is ignored.
If you want to confirm against multiple formats then look at DateTime.TryParseExact Method (String, String[], IFormatProvider, DateTimeStyles, DateTime) overload. Example from the same link:
string[] formats= {"M/d/yyyy h:mm:ss tt", "M/d/yyyy h:mm tt",
"MM/dd/yyyy hh:mm:ss", "M/d/yyyy h:mm:ss",
"M/d/yyyy hh:mm tt", "M/d/yyyy hh tt",
"M/d/yyyy h:mm", "M/d/yyyy h:mm",
"MM/dd/yyyy hh:mm", "M/dd/yyyy hh:mm"};
string[] dateStrings = {"5/1/2009 6:32 PM", "05/01/2009 6:32:05 PM",
"5/1/2009 6:32:00", "05/01/2009 06:32",
"05/01/2009 06:32:00 PM", "05/01/2009 06:32:00"};
DateTime dateValue;
foreach (string dateString in dateStrings)
{
if (DateTime.TryParseExact(dateString, formats,
new CultureInfo("en-US"),
DateTimeStyles.None,
out dateValue))
Console.WriteLine("Converted '{0}' to {1}.", dateString, dateValue);
else
Console.WriteLine("Unable to convert '{0}' to a date.", dateString);
}
// The example displays the following output:
// Converted '5/1/2009 6:32 PM' to 5/1/2009 6:32:00 PM.
// Converted '05/01/2009 6:32:05 PM' to 5/1/2009 6:32:05 PM.
// Converted '5/1/2009 6:32:00' to 5/1/2009 6:32:00 AM.
// Converted '05/01/2009 06:32' to 5/1/2009 6:32:00 AM.
// Converted '05/01/2009 06:32:00 PM' to 5/1/2009 6:32:00 PM.
// Converted '05/01/2009 06:32:00' to 5/1/2009 6:32:00 AM.

Use DateTime.TryParseExact() if you want to match against a specific date format
string format = "ddd dd MMM h:mm tt yyyy";
DateTime dateTime;
if (DateTime.TryParseExact(dateString, format, CultureInfo.InvariantCulture,
DateTimeStyles.None, out dateTime))
{
Console.WriteLine(dateTime);
}
else
{
Console.WriteLine("Not a date");
}

[TestCase("11/08/1995", Result= true)]
[TestCase("1-1", Result = false)]
[TestCase("1/1", Result = false)]
public bool IsValidDateTimeTest(string dateTime)
{
string[] formats = { "MM/dd/yyyy" };
DateTime parsedDateTime;
return DateTime.TryParseExact(dateTime, formats, new CultureInfo("en-US"),
DateTimeStyles.None, out parsedDateTime);
}
Simply specify the date time formats that you wish to accept in the array named formats.

So this question has been answered but to me the code used is not simple enough or complete. To me this bit here is what I was looking for and possibly some other people will like this as well.
string dateString = "198101";
if (DateTime.TryParse(dateString, out DateTime Temp) == true)
{
//do stuff
}
The output is stored in Temp and not needed afterwards, datestring is the input string to be tested.

An alternative is to create a method to validate that the text is of Date type.
public bool IsDateTime(string date)
{
if (string.IsNullOrEmpty(date)) return false;
return DateTime.TryParse(date, out DateTime dateTime);
}

Basically, I want to check if a particular string contains AT LEAST day(1 through 31 or 01 through 31),month(1 through 12 or 01 through 12) and year(yyyy or yy) in any order, with any date separator , what will be the solution?
So, if the value includes any parts of time, it should return true too. I could NOT be able to define a array of format.
When I was in a similar situation, here is what I did:
Gather all the formats my system is expected to support.
Looked at what is common or can be generalize.
Learned to create REGEX (It is an investment of time initially but pays off once you create one or two on your own). Also do not try to build REGEX for all formats in one go, follow incremental process.
I created REGEX to cover as many format as possible.
For few cases, not to make REGEX extra complex, I covered it through DateTime.Parse() method.
With the combination of both Parse as well as REGEX i was able to validate the input is correct/as expected.
This http://www.codeproject.com/Articles/13255/Validation-with-Regular-Expressions-Made-Simple
was really helpful both for understanding as well as validation the syntax for each format.
My 2 cents if it helps....

Try using
DateTime.ParseExact(
txtPaymentSummaryBeginDate.Text.Trim(),
"MM/dd/yyyy",
System.Globalization.CultureInfo.InvariantCulture
);
It throws an exception if the input string is not in proper format, so in the catch section you can return false;

C# Datetime format conversion

I have a conversion problem with datetime. I have a date string as MM/dd/yyyy. Now I need to convert it to yyyy-MM-dd.
But I'm facing some error. Please help
public static DateTime ToDBDateTime(string _dateTime)
{
string sysFormat = "MM/dd/yyyy hh:mm:ss tt";
string _convertedDate = string.Empty;
if (_dateTime != null || _dateTime != string.Empty)
{
_convertedDate = DateTime.ParseExact(_dateTime, sysFormat, System.Globalization.CultureInfo.InvariantCulture).ToString(_toDBDateFormat);
//_convertedDate = Convert.ToDateTime(_dateTime).ToString(_toDBDateFormat);
/// Debug.Print(sysFormat);
}
return Convert.ToDateTime(_convertedDate);
}
And I want to know that is there is any way to pass the datetime in various formats and it would return the expected format.
E.g.: if I pass date as dd/MM/yyyy or MM/dd/yyyy, the above function would return the date in format as yyyy-MM-dd.
Please provide some suggestion to solve datetime issues.

I have a date string as MM/dd/yyyy
Right... and yet you're trying to parse it like this:
string sysFormat = "MM/dd/yyyy hh:mm:ss tt";
...
_convertedDate = DateTime.ParseExact(_dateTime, sysFormat,
CultureInfo.InvariantCulture)
You need to give a format string which matches your input - so why are you including a time part? You probably just want:
string sysFormat = "MM/dd/yyyy";
However, that's not the end of the problems. You're then converting that DateTime back into a string like this:
.ToString(_toDBDateFormat)
... and parsing it once more:
return Convert.ToDateTime(_convertedDate);
Why on earth would you want to do that? You should avoid string conversions as far as possible. Aside from anything else, what's to say that _toDBDateFormat (a variable name which raises my suspicions to start with) and Convert.ToDateTime (which always uses the current culture for parsing) are going to be compatible?
You should:
Work out how you want to handle being given an empty string or null, and just return an appropriate DateTime then
Otherwise, just parse using the right format.
This part of your question also concerns me:
E.g.: if I pass date as dd/MM/yyyy or MM/dd/yyyy, the above function would return the date in format as yyyy-MM-dd.
There's no such thing as "the date in format as yyyy-MM-dd". A DateTime is just a date and time value. It has no intrinsic format. You specify how you want to format it when you format it. However, if you're using the value for a database query, you shouldn't be converting it into a string again anyway - you should be using parameterized SQL, and just providing it as a DateTime.

As you have a date in a string with the format "MM/dd/yyyy" and want to convert it to "yyyy-MM-dd" you could do like this:
DateTime dt = DateTime.ParseExact(dateString, "MM/dd/yyyy", CultureInfo.InvariantCulture);
dt.ToString("yyyy-MM-dd");

Use the inbuilt tostring like this:
Convert.ToDateTime(_convertedDate).ToString("MM/dd/yyyy") or whatever format you want.

I tried this and its working fine.
DateTime date1 = new DateTime(2009, 8, 1);
date1.ToString("yyyy-MM-dd hh:mm:ss tt");
You can apply any format in this ToString.
Hope that helps
Milind

Detect format Date

Is there a way, a good way, to test if a string than I want to transform in DateTime is dd/MM/yyyy or MM/dd/yyyy ?
Thanks,

No, because it could be both. Is 11/10/2010 November 10th or October 11th?
Yes, in some cases (if one number is above 12) it will be unambiguous - but I think it's better to force one format or the other. If you just treat anything which can be done as MM/dd/yyyy that way, and move on to dd/MM/yyyy if it fails (or the other way round) then you'll get some very surprised users.
If this is part of a web application or something similar, I would try to make it completely unambiguous by using month names instead of numbers where possible.

No, but you could try both when parsing:
DateTime result;
if (DateTime.TryParseExact(
"05/10/2010",
new[] { "MM/dd/yyyy", "dd/MM/yyyy" },
CultureInfo.InvariantCulture,
DateTimeStyles.None,
out result)
)
{
// successfully parsed date => use the result variable
}

This problem will exist until all accepts and uses the ISO way. I'm a Swedish programmer working a lot with American and English clients and it's surprisingly hard to get these clients to use the standardized date format.
ISO 8601 - Use it!

Take a look at DateTime.ParseExact and DateTime.TryParseExact.
string date1 = "24/12/2010";
CultureInfo provider = CultureInfo.InvariantCulture;
DateTime dt1 = new DateTime(1, 1, 1);
bool dt1Valid = false;
try
{
dt1 = DateTime.ParseExact(date1, "dd/MM/yyyy", provider);
dt1Valid = true;
}
catch
{
dt1Valid = false;
}