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Formatting DateTime - ignore culture

I need to format a date to the following format:
M-d-yyyy
I tried using:
string.Format("{0:M-d-yyyy}", DateTime.Now)
But the output string will depend on the CurrentCulture on the computer where it's run, so sometimes the output might be 07/09/2014 or 07.09.2014 instead of 09-07-2014.
How can I easily prevent it from converting it based on the culture and treating it as a literal string?

Use CultureInfo.InvariantCulture as the culture or provider argument.
String.Format(CultureInfo.InvariantCulture, "{0:M-d-yyyy}", DateTime.Now)

Use CultureInfo.InvariantCulture as an IFormatProvider parameter:
DateTime.Now.ToString("M-d-yyyy", CultureInfo.InvariantCulture);

You can set the culture of your program with this:
Thread.CurrentThread.CurrentCulture = System.Globalization.CultureInfo.InvariantCulture;`
You can also use a specific culture if you want (I think en-US is the one you need)

Use the following:
DateTime.Now.ToString("d", DateTimeFormatInfo.InvariantInfo);
or apply other formatting specs as detailed in http://msdn.microsoft.com/en-us/library/az4se3k1%28v=vs.110%29.aspx
Pertinent to your case it could be written as:
DateTime.Now.ToString("M-d-yyyy", DateTimeFormatInfo.InvariantInfo);
Regards,

You can use the .ToString() method on the DateTime object to format it however you'd like. Your code would look something like this:
DateTime.Now.ToString("M-d-yyyy");
More info on formatting date times can be found on the MSDN: http://msdn.microsoft.com/en-us/library/zdtaw1bw%28v=vs.110%29.aspx

you can try
date.ToString("MM/dd/yy", yyyymmddFormat);
or
try whats in this link
http://social.msdn.microsoft.com/Forums/en-US/af4f5a1e-f81d-47fe-981d-818e785b8847/convert-string-to-datetime-object
you can force the string into a standard format if you like

Exception on DateTime Conversion

I'm trying to format a list of datetime. One date is in the format same as what i provided but the factors are not in place. That line of code is given below. Can someone tell me how to skip the error for the below line?
Convert.ToDateTime("22-01-2013 00:00:00").ToString("yyyy-MM-dd");

I would avoid using Convert.ToDateTime to start with. I would suggest using DateTime.TryParse or (preferrably) DateTime.TryParseExact. Both of these will return a value indicating whether the conversion succeeded, so you don't need to start catching exceptions in order to skip bad data. For example:
DateTime parsed;
if (DateTime.TryParse(text, out parsed))
{
string reformatted = parsed.ToString("yyyy-MM-dd");
// Use reformatted
}
else
{
// Log error, perhaps?
}
If you have multiple possible formats, you should consider using the overload of TryParseExact which allows you to specify multiple formats in a single call.
As well as the format, you should consider the culture you want to use. In the above code (and your code) it will use the executing thread's culture. Is that always what you want? The culture can affect all kinds of things - usually if you're specifying a custom format, you want to use the invariant culture. Otherwise you could end up using a non-Gregorian calendar unexpectedly, for example...
EDIT: If your input is always in the format dd-MM-yyyy, then you should probably use:
DateTime parsed;
if (DateTime.TryParseExact(text, "dd-MM-yyyy", CultureInfo.InvariantCulture,
DateTimeStyles.Default, out parsed))
{
string reformatted = parsed.ToString(CultureInfo.InvariantCulture,
"yyyy-MM-dd");
// Use reformatted
}
else
{
// Log error, perhaps?
}

Instead of Convert.ToDateTime use DateTime.Parse or DateTime.ParseExact
ParseExact gives you more control over the format, so for example:
DateTime.ParseExact("22-01-2013 00:00:00","dd-MM-yyyy HH:mm:ss",CultureInfo.InvariantCulture).ToString("yyyy-MM-dd");
There is also a TryParseExact variant, which allows you to gracefully handle parse errors.

Try with:
DateTime.ParseExact("22-01-2013 00:00:00","dd-MM-yyyy HH:mm:ss",CultureInfo.InvariantCulture).ToString("yyyy-MM-dd");
This way you can specify the exact format for your date-string.

Try to use DateTime.ParseExact() method instead of.
Converts the specified string representation of a date and time to its
DateTime equivalent.
public static void Main(string[] args)
{
Console.WriteLine(DateTime.ParseExact("22-01-2013 00:00:00", "dd-MM-yyyy HH:mm:ss", CultureInfo.CurrentCulture).ToString("yyyy-MM-dd"));
}
Here is a DEMO.
Also check out Coding Best Practices Using DateTime in the .NET Framework which I think every .NET developer should read.

C# String to DateTime

DateTime frm_datestart = DateTime.Parse(dateStart.Text);
This line throws the error:
Exception Details:
System.FormatException: String was not
recognized as a valid DateTime.
Where the entered string is from Jquery-UI, examples:
09/29/2010
09/30/2010
Anyone know what the correct format should be? I'm suprised this isn't working :S

You can use an overloaded version of the DateTime.Parse() method which accepts a second DateTimeFormatInfo parameter.
System.Globalization.DateTimeFormatInfo dti = new System.Globalization.DateTimeFormatInfo();
dti.ShortDatePattern = "MM/dd/yyyy";
DateTime dt = DateTime.Parse(dateStart.Text, dti);

look for DateTime.ParseExact method.

val = dateStart.Text.ToString("yyyy-M-d HH:mm:ss");

Use DateTime.ParseExact to specify format like this: DateTime.Parse("dd/MM/yyyy", dateStart.Text, null)

The problem with DateTime.ParseExact() method suggested in previous answers is, it fails on some Cultures. So your application may fail to run correctly on certain Operating Systems.
If you are sure that dateStart.Text will always be in the same format (i.e. en-US), you may try passing appropriate CultureInfo as a second argument. For format "MM/dd/yyyy" use CultureInfo.InvariantCulture.

converting string to valid datetime

string strdate="15/06/2010";
DateTime dt =
DateTime.Parse(strdate,
System.Threading.Thread.CurrentThread.CurrentCulture.DateTimeFormat);
i cannot able to get the datetime value as dd/mm/yyyy.
it is giving exception 'string is not recognized as a valid datetime'
oly if it is in 06/15/2010 it is working. how to get the same format in dt.

Well, presumably your thread's current culture expects MM/dd/yyyy. If you want to use dd/MM/yyyy then you should specify that explicitly. Personally I prefer ParseExact instead of Parse, as that gives more control. I would use something like:
DateTime dt = DateTime.ParseExact(strdate, "dd/MM/yyyy",
CultureInfo.InvariantCulture);
Note that if this is user input, you may want to use TryParseExact instead.

You're currently using the current culture, which seems to be set up for US style date formats. Try this instead:
DateTime.Parse(strdate, System.Globalization.CultureInfo.CreateSpecificCulture("en-GB"));
This tells the function to use UK date style format which works. You might want to change the en-GB to whatever culture your dates will be in. If you have many calls where the culture is important it might also be worth to set it for the whole thread rather than call by call.

Parsing exact dates in C# shouldn't force you to create an IFormatProvider

Someone please correct me if I'm wrong, but parsing a yyyy/MM/dd (or other specific formats) dates in C# should be as easy as
DateTime.ParseExact(theDate, "yyyy/MM/dd");
but no, C# forces you to create an IFormatProvider.
Is there an app.config friendly way of setting this so I don't need to do this each time?
DateTime.ParseExact(theDate, "yyyy/MM/dd", new CultureInfo("en-CA", true));

The IFormatProvider argument can be null.

ParseExact needs a culture : consider "yyyy MMM dd". MMM will be a localized month name that uses the current culture.

Use the current application culture:
DateTime.ParseExact("2008/12/05", "yyyy/MM/dd", System.Globalization.CultureInfo.CurrentCulture);
You can set the application culture in the app.config using the Globalization tag. I think.

Create an extension method:
public static DateTime ParseExactDateTime(this string dateString, string formatString) {
return DateTime.ParseExact(dateString, formatString, new CultureInfo("en-CA", true));
}

It requires the format provider in order to determine the particular date and time symbols and strings (such as names of the days of the week in a particular language). You can use a null, in which case the CultureInfo object that corresponds to the current culture is used.
If you don't want to have to specify it each time, create an extension method which either passes null or CultureInfo("en-CA", true) as the format provider.

You could also simply create the IFormatProvider once and store it for later use.

You could also use the Convert class
Convert.ToDateTime("2008/11/25");

//Convert date to MySql compatible format
DateTime DateValue = Convert.ToDateTime(datetimepicker.text);
string datevalue = DateValue.ToString("yyyy-MM-dd");

What's wrong with using Globalization.CultureInfo.InvariantCulture ?