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C# Parse to the yyyy-MM-ddTHH:mm:ss format String was not recognized as a valid DateTime

I'm trying to Parse Mon, 11 Mar 2019 09:13:16 +0100 to 2019-03-11T09:13:16
string dataa = "Mon, 11 Mar 2019 09:13:16 +0100";
DateTime d = new DateTime();
d = DateTime.ParseExact(dataa,"yyyy-MM-ddTHH:mm:ss", System.Globalization.CultureInfo.InvariantCulture);
Console.WriteLine("data: "+d);
But the error is:
String was not recognized as a valid DateTime.
Is there any method to do this parsing automatically? Thanks to everyone.
update
As mentioned below, like the other users replied to me, I needed the function ToString(String, IFormatProvider) in the first place.

When you use ParseExact, your string and format should match exactly.
The proper format is: ddd, d MMM yyyy hh:mm:ss zzz (or HH which depends on your hour format)
After you parse it, you need to use ToString to format it with yyyy-MM-dd'T'hh:mm:ss format (or HH which depends you want 12-hour clock or 24-hour clock format)
I think I have to add little bit more explanation that a lot of people confuse (specially who are beginner about programming). A DateTime instance does not have any format. It just have date and time values which is basicly a numeric value called Ticks. When you talk about "format" concept, that points to textual representation which is string.
Since you said "Mon, 11 Mar 2019 09:13:16 +0100 to 2019-03-11T09:13:16", I (and probably a lot of people also) assume that you have a string as Mon, 11 Mar 2019 09:13:16 +0100 and you want to get 2019-03-11T09:13:16 as a string from it. For that, you need to parse your string to DateTime first. For that, as you do, ParseExact is one option.
When you parse it to DateTime, you get it's textual representation, which is string, with ToString method. This method have a few overloads and you should use ToString(String, IFormatProvider) overload. With that, you specify your output format as a first parameter, and your culture info as a second parameter which it might effect on your result string because of the : and / format specifiers since they can change based on the current culture or supplied culture.
Further reading: Custom Date and Time Format Strings

You need to specify the format that the input data has (the second parameter of DateTime.ParseExact). In your case, the data you provide has the format ddd, d MMM yyyy hh:mm:ss zzz. Also, in the last line, where you print the result you have to format it.
So, this is how you have to do it:
string dataa = "Mon, 11 Mar 2019 09:13:16 +0100";
DateTime d = new DateTime();
d = DateTime.ParseExact(dataa, "ddd, d MMM yyyy hh:mm:ss zzz", System.Globalization.CultureInfo.InvariantCulture);
Console.WriteLine("data: " + d.ToString("yyyy-MM-dd'T'hh:mm:ss"));

Parse Date Time from US Time zone to Datetime.

How to parse below date time string?
2014-01-17T09:59:24.000Z
I tried below code but its, not working.
DateTime.ParseExact("2014-01-17T09:59:24.000Z", "ddd MMM dd HH:mm:ss %zzzz yyyy", CultureInfo.InvariantCulture);

With a string like "2014-01-17T09:59:24.000Z"
You can just use DateTime.Parse("2014-01-17T09:59:24.000Z")
From The Documentation:
The string to be parsed can take any of the following forms:
A string that includes time zone information and conforms to ISO 8601. In the following examples, the first string designates Coordinated Universal Time (UTC), and the second string designates the time in a time zone that's seven hours earlier than UTC:
2008-11-01T19:35:00.0000000Z
2008-11-01T19:35:00.0000000-07:00

From DateTime.ParseExact
Converts the specified string representation of a date and time to its
DateTime equivalent using the specified format and culture-specific
format information. The format of the string representation must match
the specified format exactly.
Clearly your string representation and format is not the same.
You can use it like;
var date = DateTime.ParseExact("2014-01-17T09:59:24.000Z",
"yyyy-MM-dd'T'HH:mm:ss.fff'Z'",
CultureInfo.InvariantCulture);
Console.WriteLine(date);
Output will be;
1/17/2014 9:59:24 AM
Here a demonstration.
For more information, take a look at;
Custom Date and Time Format Strings

The value you have, 2014-01-17T09:59:24.000Z is an ISO8601/RFC3339 formatted timestamp. The Z at the end is significant, which means that it represents UTC.
You have two options to correctly parse it:
You could parse it to a DateTime that has DateTimeKind.Utc for it's .Kind property:
DateTime dt = DateTime.ParseExact("2014-01-17T09:59:24.000Z",
"yyyy-MM-dd'T'HH:mm:ss.fffK",
CultureInfo.InvariantCulture,
DateTimeStyles.RoundtripKind);
Or, you could parse it to a DateTimeOffset, where UTC will correspond to an offset of zero:
DateTimeOffset dt = DateTimeOffset.ParseExact("2014-01-17T09:59:24.000Z",
"yyyy-MM-dd'T'HH:mm:ss.fffK",
CultureInfo.InvariantCulture);
Some of the other answers here are close, but are forgetting to actually consider the Z in your string, using the K specifier and the DateTimeStyles.RoundtripKind parameter. These are important, for without them you will likely end up with a resulting DateTime that has DateTimeKind.Unspecified, which could get treated as local time in certain time zone conversion functions. If you use either of the options I gave you, then the meaning of the Z is preserved.

How do I parse an RFC822 date in .NET?

I have the following datetime string as returned to me by the Twitter API:
"Thu Apr 26 11:38:36 +0000 2012"
I need to convert this to a DateTime object so I call ParseExact with a custom format specifier:
CultureInfo provider = CultureInfo.InvariantCulture;
DateTime publishDate = DateTime.ParseExact(tweet["created_at"].ToString(), "ddd MMM dd hh:mm:ss zzz yyyy", provider);
However, this raise a FormatException exception for any variant of z, zz or zzz for the time zone:
String was not recognized as a valid DateTime.
Looking at the MSDN documentation it's clear that that format specifier is expecting the time zone to be in the format zz:zz where there is a colon in the time zone to delimit the hours and minutes.
I've checked other questions on Stack Overflow like:
How do I parse and convert DateTime’s to the RFC 822 date-time format?
Parsing an RFC822-Datetime in .NETMF 4.0
and none of them really help.
Is there a time zone specifier I can use that will correctly parse this format?

Really silly this one.
The problem was the hour specifier. I'd used "hh" which is for 12 hour clock times. For 24 hour times I should have used "HH".
Note the subtle difference.
Changing that it all works as expected.

Trying to parse a DateTime in C#

I am trying to parse a DateTime in C# and have the following lines of code:
string dt =Convert.ToString( DateTime.FromFileTime(e8.sts[counter8].TimeStamp));
string format = "dd-MM-yyyy HH:mm:ss";
DateTime dateTime = DateTime.ParseExact(dt, format,CultureInfo.InvariantCulture);
When I debug dt is coming in as 05/18/2011 09:25:17 AM but I get an expection saying:
String was not recognized as a valid
DateTime.

Starting off, you have no need for the conversion.
DateTime.FromFileTime(e8.sts[counter8].TimeStamp) returns a DateTime already...
Even so, with the string you have provided, DateTime.Parse(str) will take care of you.
If you end up storing this value in a text file, and really are dead-set on using a custom format string to parse it (which you don't need to):
The format you have:
Day/Month/Year 24-hour:minute:second
But looking at your input date:
05/18/2011 09:25:17 AM
You want:
Month/Day/Year 12-hour:minutes:seconds AM/PM
The format for what you want is:
MM/dd/yyyy hh:mm:ss tt

Isn't this expected? Date 05/18/2011 09:25:17 AM doesn't match your format string dd-MM-yyyy HH:mm:ss. Your date is in format MM/dd/yyyy HH:mm:ss tt.
Try this:
DateTime dateTime = DateTime.Parse("05/18/2011 09:25:17 AM");

I don't see any reason for the conversion. Just use:
DateTime.FromFileTime(e8.sts[counter8].TimeStamp)

Your DateTime is coming in as MM-dd-yyyy but you are trying to parse it as dd-MM-yyyy
Change your format string to "MM-dd-yyyy HH:mm:ss tt"
You can tell this as dt, using your current format string, is trying to be parsed as the 5th day (dd) of the 18th month (MM) of 2011 (yyyy)...
EDIT:
Sorry, I completely missed the AM/PM designator, you need the tt part of the format string. This will handle the AM/PM part of the string
EDIT 2:
As per your most recent comment, you want to convert it into MM-dd-yyyy HH:mm:ss string, the all you need to do is:
var outputString = DateTime.FromFileTime(e8.sts[counter8].TimeStamp).ToString("MM-dd-yyyy HH:mm:ss");
You already have the TimeStamp in a val;id .NET DateTime object, so all you need to do is perform a .ToString() with the required time format.

DateTime parsed = DateTime.ParseExact(dt,"MM/dd/yyyy HH:mm:ss tt",CultureInfo.InvariantCulture);

s many of the others have explained here, the format needs to be changed. However even when I tried the formats they have suggested, I still received the same error that you did. Eventually I hit upon the right format to get successful results.
The format should be:
string format = "MM/dd/yyyy HH:mm:ss tt";
because you are specifying time pattern such as AM. If the month is given as single digit, eg: 5, then MM should be replaced with M. I used slash instead of hypen between the dates because that's how the original date had been given.

how do I specify the timezone on a DateFormat string?

I'm trying to specify the timezone on a string that I am passing to DateFormat.parse. We're currently using .net framework 2.0. Current code is
DateTimeFormatInfo DATE_FORMAT = CultureInfo.CurrentCulture.DateTimeFormat;
DateTime first = DateTime.Parse("Wed, 31 Oct 2007 8:00:00 -5", DATE_FORMAT);
But then when I do first.ToString("r"), the result is
Wed, 31 Oct 2007 09:00:00 GMT
What am I doing wrong? I also tried using DateTime.SpecifyKind method to set my DateTime object's Kind to Local, but it seems like you would need to specify the kind as local before you parse the string, if the timezone is part of the string.
My local timezone is EDT, that's what I'm ultimately trying to get this date to.
Edit - our solution:
input :
DateTime first = DateTime.SpecifyKind(DateTime.Parse("OCT 31, 2007 8:00 AM", DATE_FORMAT), DateTimeKind.Local);
output :
first.ToLocalTime().ToString("our format")
Still haven't found a way to get time zone abbreviation, like 'EDT'.

Use the ToLocalTime() method before calling ToString().
first.ToLocalTime().ToString();

You can use the "zz" or "zzz" date formats to give you -5 or -5:00.

When you call first.ToString("r"),
Here is what based on MSDN
Represents a custom date and time
format string defined by the
DateTimeFormatInfo..::.RFC1123Pattern
property. The pattern reflects a
defined standard and the property is
read-only. Therefore, it is always the
same, regardless of the culture used
or the format provider supplied. The
custom format string is "ddd, dd MMM
yyyy HH':'mm':'ss 'GMT'".
You can pass the defined format information into ToString, try to call this method
DateTime..::.ToString Method (IFormatProvider)
Instead, and pass your DateTimeFormatInfo object.

Have a look at the DateTimeOffset struct, I think this is what you need.

Try using ParseExact() - you can specify what goes where.
In your case, you can parse it with:
string str = "Wed, 31 Oct 2007 8:00:00 -5";
string fmt = "ddd, dd MMM yyyy H:mm:ss z";
DateTime d = DateTime.ParseExact(str, fmt, null);
Console.WriteLine(d);