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Parsing horrible timestamp C#

I have a timestamp from a server of the form 20220505 17:36:29 - it has 2 whitespaces, and I do not trust the sender to always send the same number of whitespaces in future revisions - ideally would like to handle any number of whitespaces the same.
I tried this with DateTime.ParseExact but failed:
var horribleTimestamp = "20220505 17:36:29";
var timestamp = DateTime.ParseExact(horribleTimestamp, "yyyyMMdd hh:mm:ss", CultureInfo.InvariantCulture)
// throws `System.FormatException: String '20220505 17:36:29' was not recognized as a valid DateTime.`
To save my headaches with timezones later how can I achieve this with Nodatime as i think makes sense to switch to that already.
The time is local from my PC and I would like to convert this to a global timestamp (which I believe should be Instant?) for a given local timezone?

If you want to handle any amount of whitespace, there are two options:
Use a regular expression (or similar) to get it into a canonical format with a single space
Split on spaces and then parse the first and last parts separately. (Or split on spaces, recombine the first and last parts and parse...)
In Noda Time, the value you've got represents a LocalDateTime, so that's what you should parse it to. Here's a complete example using the regex approach:
using NodaTime;
using NodaTime.Text;
using System.Text.RegularExpressions;
// Lots of spaces just to check the canonicalization
string text = "20220505 17:36:29";
// Replace multiple spaces with a single space.
string canonicalized = Regex.Replace(text, " +", " ");
// Note: patterns are immutable; you should generally store them in
// static readonly fields. Note that "uuuu" represents an absolute year number,
// whereas "yyyy" would be "year of era".
LocalDateTimePattern pattern =
LocalDateTimePattern.CreateWithInvariantCulture("uuuuMMdd HH:mm:ss");
ParseResult<LocalDateTime> result = pattern.Parse(canonicalized);
// Note: if you're happy with an exception being thrown on a parsing failure,
// juse use result.Value unconditionally. The approach below shows what to do
// if you want to handle parse failures without throwing an exception (or with
// extra behavior).
if (result.Success)
{
LocalDateTime value = result.Value;
Console.WriteLine(value);
}
else
{
// You can also access an exception with more information
Console.WriteLine("Parsing failed");
}

You can pass multiple formats to ParseExact as an array
var horribleTimestamp = "20220505 17:36:29";
var formats = new[]{"yyyyMMdd HH:mm:ss","yyyyMMdd HH:mm:ss","yyyyMMdd HH:mm:ss"};
var timestamp = DateTime.ParseExact(horribleTimestamp, formats, CultureInfo.InvariantCulture, 0);
dotnetfiddle

You have an error in your format. use HH instead of hh. See updated code below
var horribleTimestamp = "20220505 17:36:29";
var timestamp = DateTime.ParseExact(horribleTimestamp, "yyyyMMdd HH:mm:ss", CultureInfo.InvariantCulture)
Here is y link that explains what you can use in a format -> https://www.c-sharpcorner.com/blogs/date-and-time-format-in-c-sharp-programming1

You can solve the problem with the whitespaces in this way:
var horribleTimestamp = "20220505 17:36:29";
var date = horribleTimestamp.Substring(0, 8);
var index = horribleTimestamp.LastIndexOf(' ') + 1;
var time = horribleTimestamp.Substring(index, horribleTimestamp.Length - index);
var timestamp = DateTime.ParseExact($"{date} {time}", "yyyyMMdd HH:mm:ss", CultureInfo.InvariantCulture);
I suppose that date has always 8 characters and that space is always present. In other case, check index == -1.

Parsing double with dot to comma

I am working with doubles. In the Netherlands we make use of 51,3 instead of 51.3. I did write a piece of code that works with dots instead of commas. But the result of the previously written code returns a double the English way, with a dot. I am encountering some strange errors.
Here is what I have:
var calResult = 15.2d;
var calResultString = calResult.ToString(CultureInfo.GetCultureInfo("nl-NL"));
var result = double.Parse(calResultString);
calResult == "15.2" -> as expected
calResultString == "15,2" -> as expected
result == "152" -> here I expect a comma.
A also did try to add the cultureinfo also in the double.Parse. This resulted in a "15.2".
TLDR: I need to convert an English/American double to a Dutch(or similar rules) one.
Thanks in advance! :)
P.S
I hope this is not a duplicate question, but didn't found anything this specific.

You, probably, should either provide "nl-NL" whenever you work with Netherlands' culture
var calResult = 15.2d;
var calResultString = calResult.ToString(CultureInfo.GetCultureInfo("nl-NL"));
// We should parse with "nl-NL", not with CurrentCulture which seems to be "en-US"
var result = double.Parse(calResultString, CultureInfo.GetCultureInfo("nl-NL"));
Or specify CurrentCulture (default culture)
CultureInfo.CurrentCulture = CultureInfo.GetCultureInfo("nl-NL");
var calResult = 15.2d;
// now CultureInfo.GetCultureInfo("nl-NL") is redundant
var calResultString = calResult.ToString();
var result = double.Parse(calResultString);
Finally, if you have a string which represents some floating point value in en-US culture, and you want the same value but be a string in nl-NL format:
string source = "123.456";
string result = double
.Parse(source, CultureInfo.GetCultureInfo("en-US"))
.ToString(CultureInfo.GetCultureInfo("nl-NL"));

Numbers and strings don't contain any culture information, instead you specify the culture when you convert between numbers and strings.
result == "152" -> here I expect a comma
What happened is that you asked the operating system to parse "15,2" into a double, and didn't specify a culture. It defaulted to US culture and ignored the comma.
If you'd specified a culture:
var result = double.Parse(calResultString, CultureInfo.GetCultureInfo("nl-NL"));
it would have given you the right value (15.2), and that might even have been displayed as 15,2 if your computer was configured to the right number format (and the debugger used your preference).
Ideally you don't hard-code the culture, but use the culture that the user has chosen.

I've written a simple method that will check for the coma character in your input and replace it with a dot. I believe the best way is to take an input as a string value. this way you can manipulate it and then you can parse it and return a double or a string if you wish:
var input = Console.ReadLine();
double parsedDouble;
if (input.Contains(","))
{
input = input.ToString().Replace(",", ".");
}
if (!Double.TryParse(input, out parsedDouble))
{
Console.WriteLine("Error parsing input");
}
else
{
Console.WriteLine(parsedDouble);
}
Console.ReadLine();
edit: the answers from Robin Bennett/Dmitry Bychenko are much better than mine, as mine is just more manual. I wasn't aware of the overload of parse that he had provided.
I'll leave my solution, cause it does solve this issue, even if it's a bit more... brute ;)

var calResult = 15.2d;
var calResultString = calResult.ToString();
string result = double.Parse(calResultString).ToString(CultureInfo.GetCultureInfo("nl-NL"));

Contains doen't check in the date range

I have a date range come like this,
string ActualReleaseDates ="7/8/2016, 7/9/2016, 7/11/2016,7/3/2016,7/10/2016,7/17/2016,7/24/2016,7/31/2016";
string NewsReleasedDate ="07/11/2016";
I want to check NewsReleaseDate is inside the ActualReleaseDates
But in the following code it return as a false.
if (ActualReleaseDates.Split(',').Contains(NewsReleasedDate.TrimStart(new Char[] { '0' })))
{
//some code here
}

The immediate problem is that after splitting your ActualReleaseDates string, there isn't an entry of "7/11/2016"... instead, there's an entry of " 7/11/2016"... note the space.
But more fundamentally, just trimming the start of NewsReleasedDate won't help if the value is something like "07/08/2016"... what you should be doing is handling these values as dates, rather than as strings:
Split ActualReleaseDates by comma, then parse each value (after trimming whitespace) in an appropriate format (which I suspect is M/d/yyyy) so that you get a List<DateTime>.
Parse NewsReleasedDate in the appropriate format, which I suspect is MM/dd/yyyy, so you get a DateTime.
See whether the parsed value from the second step occurs in the list from the first step.
(I'd personally recommend using Noda Time and parsing to LocalDate values, but I'm biased...)
Fundamentally, you're trying to see whether one date occurs in a list of dates... so make sure you get your data into its most appropriate representation as early as possible. Ideally, avoid using strings for this at all... we don't know where your data has come from, but if it started off in another representation and was converted into text, see if you can avoid that conversion.

The white space problem. You can use trim() and ' 7/11/2016' will be '7/11/2016'
var ActualReleaseDates = "7/8/2016, 7/9/2016, 7/11/2016,7/3/2016,7/10/2016,7/17/2016,7/24/2016,7/31/2016";
var NewsReleasedDate = "07/11/2016";
var splitActualReleaseDates = ActualReleaseDates.Split(',').Select(x => x.Trim());
if (splitActualReleaseDates.Contains(NewsReleasedDate.TrimStart(new Char[] { '0' })))
{
}

You can use linq to convert your strings into DateTime objects and compare them instead of strings
string ActualReleaseDates ="7/8/2016,7/9/2016,7/11/2016,7/3/2016,7/10/2016,7/17/2016,7/24/2016,7/31/2016";
string NewsReleasedDate ="07/11/2016";
var releaseDates = ActualReleaseDates.Split(',').Select(x => DateTime.Parse(x));
var newsReleased = DateTime.Parse(NewsReleaseDate);
if (releaseDates.Contains(newsReleased))
{
//some code here
}
please note that DateTime is parsed respectively to the current Culture. You can use DateTime.ParseExact if you want to specify exact date format.

You can Prase to DateTime before doing the query like this:
(I think this is the most accurate and guaranteed way to compare dates)
Func<string, DateTime> stringToDate = s => DateTime.ParseExact(s.Trim(), "M/d/yyyy",
CultureInfo.InvariantCulture);
DateTime newReleaseDateTime = stringToDate(NewsReleasedDate);
bool result = ActualReleaseDates.Split(',').Select(x => stringToDate(x))
.Contains(newReleaseDateTime);

It returns false because of the date 07/11/2016 stored in NewsReleasedDate is stored as string with a '0' at the begining. And in the ActualReleaseDates string you have white spaces between the ',' and numbers.
Try to rewrite theese strings like this :
ActualReleaseDates ="7/8/2016,7/9/2016,7/11/2016,7/3/2016,7/10/2016,7/17/2016,7/24/2016,7/31/2016"; // white spaces removed.
and the variable like this :
NewsReleasedDate ="7/11/2016"; // 0 removed
This is my code example :
string ActualReleaseDates = "7/8/2016,7/9/2016,7/11/2016,7/3/2016,7/10/2016,7/17/2016,7/24/2016,7/31/2016";
string NewsReleasedDate = "7/11/2016";
string[] dates = ActualReleaseDates.Split(',');
Console.WriteLine(dates.Contains(NewsReleasedDate));
This is not the best way to compare dates, you can use Date class which is usefull to do this kind of comparations.

How to prevent inserted currency sign if value is 0?

I want to ask is there a way to prevent dollar sign to be inserted if the value is 0?
I am using string function Format to make currency sign #string.Format("{0:C}",0)) update my output is $0.00

Make an extension method to do this:
public static string ToCurrency(this int value)
{
return value == 0 ? value.ToString("N2") : value.ToString("C");
}

You can use a three-part custom format string with ; separating the different sections. The first section describes the format applied to positive numbers; the second applies to negative numbers; and the third applies to zero:
const string format = "{0:$#,0.00;-$#,0.00;0.00}";
string.Format(format, 1.23d) // => $1.23
string.Format(format, -1.23d) // => -$1.23
string.Format(format, 0d) // => 0.00
Sadly, this only works with custom formats, meaning you cannot use built-in specifiers like C in the individual sections. One consequence of this is that you cannot rely on the system choosing which currency symbol to include based on the thread culture; you must include it directly in the format string.

Dynamic timespan format string

I want to set my TimeSpan format string dynamically. It means if the time span value is negative format string should be different from positive one. the point that when I want to set format string I don't know the value of TimeSpan!
For example: I want to have -03:01:01 for negative timespan and 003:01:01 for positive value
the code is
columns.Add(new TimeSpanColumnInfo(col.PropertyName, col.TitlePersian, col.TitleEnglish, "ddd\\:hh\\:mm"));
witch third arguments is formatstring

Your question still isn't clear but if you have a TimeSpan object called t you can conditionally choose a format string by doing the following:
string format = t < TimeSpan.Zero ? #"\-dd\:hh\:mm" : #"ddd\:hh\:mm";
If you really need to specify the format in advance of knowing the value of t (questionable), then you could change your method signature to accept a Func<TimeSpan, string> and pass in the following as an argument:
o => o < TimeSpan.Zero ? #"\-dd\:hh\:mm" : #"ddd\:hh\:mm"
More info on Func<T, TResult>.

It sounds like you're looking for something like the section separator.
string s = someNumber.ToString("00;(00)");
In the above example, positive values are output with two digits and negative values are output with two digits wrapped in parenthesis.
Unfortunately, the section separator is only valid for custom numeric formats. The custom timespan formats do not include a section separator.