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Assign value of a string (containing date and time) to two different variable (one for Date and one for Time)

I have a string ("CompletionDate") which contains the value "2/28/2017 5:24:00 PM"
Now I have 2 variables (EDate and ETime). I want to assign the Date to EDate (i.e 2/28/2017) and Time to ETime (i.e. 5:24:00 PM).
How can I split the Date and Time from a single string.
Kindly Help.
My approach right now is like :
string CompletionDate = string.Empty;
string ProjectEDate = string.Empty;
string ProjectETime = string.Empty;
CompletionDate = "2017-03-29 12:58:00";
DateTime dt = DateTime.ParseExact(CompletionDate, "yyyy-MM-dd", CultureInfo.CreateSpecificCulture("en-us"));
DateTime dt1 = DateTime.ParseExact(CompletionDate, "HH:mm:ss", CultureInfo.CreateSpecificCulture("en-us"));
var ProjectEDate = dt.ToString();
var ProjectETime = dt1.ToString();
But its throwing exception that string is not in correct format. Kindly help

#Chris pointed one of your problems, but you have one more. You are passing full date time string and trying to treat it as date or time only, which is not true. Instead I suggest you to parse DateTime object with both date and time, and then take whatever you need from parsed object:
CultureInfo enUS = CultureInfo.CreateSpecificCulture("en-us");
DateTime dt = DateTime.ParseExact(CompletionDate, "yyyy-MM-dd HH:mm:ss", enUS);
var ProjectEDate = dt.Date.ToString();
var ProjectETime = dt.TimeOfDay.ToString();

You need to specify the full format as same as the input string to parse method.
DateTime dt = DateTime.ParseExact(CompletionDate, "yyyy-MM-dd HH:mm:ss", System.Globalization.CultureInfo.CreateSpecificCulture("en-us"));
To get results you can use below methods available by default in DateTime.
dt.ToShortTimeString()
"12:58 PM"
dt.ToLongTimeString()
"12:58:00 PM"
dt.ToLongDateString()
"Wednesday, March 29, 2017"
dt.ToShortDateString()
"3/29/2017"
Or you can specify the format to ToString method.
dt.ToString("yyyy-MM-dd")
"2017-03-29"
dt.ToString("HH:mm:ss")
"12:58:00"

DateTime.ParseExact(CompletionDate, "yyy-MM-dd", ...
You are missing 4th 'y' in date format string:
"yyyy-MM-dd"
^
here
and:
String was not recognized as a valid DateTime " format dd/MM/yyyy"

Why do you parse into DateTime and then convert to a string using ToString again? Couldn´t you just simply use String.Split when all you want is to split the time from the day and you know the exact format?
var CompletionDate = "2017-03-29 12:58:00";
var tmp = CompletionDate.Split(' ');
var ProjectEDate = tmp[0];
var ProjectETime = tmp[1];

How to get yesterday's date in C#

I want to retrieve yesterday's date in my ASP.NET web application using C#.
I've tried searching for a solution but have not had much success. The code I'm using just outputs today's date:
string yr = DateTime.Today.Year.ToString();
string mn = DateTime.Today.Month.ToString();
string dt = DateTime.Today.Day.ToString();
date = string.Format("{0}-{1}-{2}", yr, mn, dt);
How can I get yesterday's date?

Use DateTime.AddDays() method with value of -1
var yesterday = DateTime.Today.AddDays(-1);
That will give you : {6/28/2012 12:00:00 AM}
You can also use
DateTime.Now.AddDays(-1)
That will give you previous date with the current time e.g. {6/28/2012 10:30:32 AM}

The code you posted is wrong.
You shouldn't make multiple calls to DateTime.Today. If you happen to run that code just as the date changes you could get completely wrong results. For example if you ran it on December 31st 2011 you might get "2011-1-1".
Use a single call to DateTime.Today then use ToString with an appropriate format string to format the date as you desire.
string result = DateTime.Today.AddDays(-1).ToString("yyyy-MM-dd");

You don't need to call DateTime.Today multiple times, just use it single time and format the date object in your desire format.. like that
string result = DateTime.Now.Date.AddDays(-1).ToString("yyyy-MM-dd");
OR
string result = DateTime.Today.AddDays(-1).ToString("yyyy-MM-dd");

You will get yesterday date by this following code snippet.
DateTime dtYesterday = DateTime.Now.Date.AddDays(-1);

var yesterday = DateTime.Now.AddDays(-1);

Something like this should work
var yesterday = DateTime.Now.Date.AddDays(-1);
DateTime.Now gives you the current date and time.
If your looking to remove the the time element then adding .Date constrains it to the date only ie time is 00:00:00.
Finally .AddDays(-1) removes 1 day to give you yesterday.

string result = DateTime.Now.Date.AddDays(-1).ToString("yyyy-MM-dd");

DateTime dateTime = DateTime.Now ;
string today = dateTime.DayOfWeek.ToString();
string yesterday = dateTime.AddDays(-1).DayOfWeek.ToString(); //Fetch day i.e. Mon, Tues
string result = dateTime.AddDays(-1).ToString("yyyy-MM-dd");
The above snippet will work. It is also advisable to make single instance of DateTime.Now;

DateTime.Today as it implies is todays date and you need to get the Date a day before so you subtract one day using AddDays(-1);
There are sufficient options available in DateTime to get the formatting like ToShortDateString depending on your culture and you have no need to concatenate them individually.
Also you can have a desirable format in the .ToString() version of the DateTime instance

convert string to date(dd/MM/yyyyy) format in c#

i have a query string with format MM/DD/YYYY
I am using it in c# like
DateTime d = Request.QueryString["dateTime"].toString();
its giving me a lot of error saying the date time format is not recognized. If i manually change the datetime in browser address bar (query string) to dd/mm/yyyy then the program just works fine.
I cannot change the query string, is there a way in c# to get it from browser and then convert into date like dd/mm/yyyy please?
edit:
the query string:
http://localhost:49543/HM/Admin/ViewDetails.aspx?OrderNo=10&DateCreated=08/30/2010
so you can see the datecreated part is in MM/DD/YYYY format.
I am not able to grab it from c#. If I manually change that to 30/08/2010, it works

DateTime d = DateTime.ParseExact(Request.QueryString["dateTime"], "dd/MM/yyyy", CultureInfo.InvariantCulture);

How to turn string from request into DateTime:
DateTime d = DateTime.ParseExact(Request.QueryString["dateTime"], "dd/MM/yyyy", null);

DateTime.ParseExact is the solution you seek for.
But I recommend you to validate the querystring data with a function as follows:
bool isValidDate(string dtStr) {
string pattern = #"^(([0-2]\d|[3][0-1])\/([0]\d|[1][0-2])\/[2][0]\d{2})$)";
System.Text.RegularExpressions.Regex re = new System.Text.RegularExpressions.Regex(pattern);
return re.IsMatch(dtStr);
}
EDIT 1: Besides ParseExact, you can use the following:
DateTime.Parse(dateString, new System.Globalization.CultureInfo("tr-TR"))
Turkish datetime format is dd/MM/YYYY.

// Parsing:
DateTime d = DateTime.Parse(Request.QueryString["dateTime"].toString());
// Conversion:
string dString = d.ToWhateverFormatYouWant();
And here's some info on formatting dates:
http://msdn.microsoft.com/en-us/library/az4se3k1(VS.71).aspx

DateTime.TryParse could be a great option..

Try this it should work
DateTime d =
DateTime.ParseExact(Request.QueryString["dateTime"],
"dd'/'MM'/'yyyy",
CultureInfo.InvariantCulture);
I faced something similar: DateTime Format in C#

You can use: DateTime.Now.ToString("dd/MM/yyyy");

C# Getting Just Date From Timestamp

If I have a timestamp in the form: yyyy-mm-dd hh:mm:ss:mmm
How can I just extract the date from the timestamp?
For instance, if a timestamp reads: "2010-05-18 08:36:52:236" what is the best way to just get 2010-05-18 from it.
What I'm trying to do is isolate the date portion of the timestamp, define a custom time for it to create a new time stamp. Is there a more efficient way to define the time of the timestamp without first taking out the date, and then adding a new time?

DateTime.Parse("2010-05-18 08:36:52:236").ToString("yyyy-MM-dd");

You should use the DateTime type:
DateTime original = DateTime.Parse(str);
DateTime modified = original.Date + new TimeSpan(13, 15, 00);
string str = modified.ToString("yyyy-MM-dd HH:mm:ss:fff");
Your format is non-standard, so you'll need to call ParseExact instead of Parse:
DateTime original = DateTime.ParseExact(str, "yyyy-MM-dd HH:mm:ss:fff", CultureInfo.InvariantCulture);

You could use substring:
"2010-05-18 08:36:52:236".Substring(0, 10);
Or use ParseExact:
DateTime.ParseExact("2010-05-18 08:36:52:236",
"yyyy-MM-dd HH:mm:ss:fff",
CultureInfo.InvariantCulture)
.ToString("yyyy-MM-dd");

DateTime date;
if (DateTime.TryParse(dateString, out date))
{
date = date.Date; // Get's the date-only component.
// Do something cool.
}
else
{
// Flip out because you didn't get a real date.
}

Get the .Date member on the DateTime
DateTime date = DateTime.Now;
DateTime midnightDate = date.Date;

use it like this:
var x = DateTime.Now.Date; //will give you midnight today
x.AddDays(1).AddTicks(-1); //use these method calls to modify the date to whats needed.

The best (and fastest) way to do this is to convert the date to an integer as the time part is stored in the decimal part.
Try this:
select convert(datetime,convert(int, #yourdate))
So you convert it to an integer and then back to a data and voila, time part is gone.
Of course subtracting this result from the original value will give you the time part only.

String was not recognized as a valid DateTime " format dd/MM/yyyy"

I am trying to convert my string formatted value to date type with format dd/MM/yyyy.
this.Text="22/11/2009";
DateTime date = DateTime.Parse(this.Text);
What is the problem ?
It has a second override which asks for IFormatProvider. What is this? Do I need to pass this also? If Yes how to use it for this case?
Edit
What are the differences between Parse and ParseExact?
Edit 2
Both answers of Slaks and Sam are working for me, currently user is giving the input but this will be assured by me that they are valid by using maskTextbox.
Which answer is better considering all aspects like type saftey, performance or something you feel like

Use DateTime.ParseExact.
this.Text="22/11/2009";
DateTime date = DateTime.ParseExact(this.Text, "dd/MM/yyyy", null);

You need to call ParseExact, which parses a date that exactly matches a format that you supply.
For example:
DateTime date = DateTime.ParseExact(this.Text, "dd/MM/yyyy", CultureInfo.InvariantCulture);
The IFormatProvider parameter specifies the culture to use to parse the date.
Unless your string comes from the user, you should pass CultureInfo.InvariantCulture.
If the string does come from the user, you should pass CultureInfo.CurrentCulture, which will use the settings that the user specified in Regional Options in Control Panel.

Parsing a string representation of a DateTime is a tricky thing because different cultures have different date formats. .Net is aware of these date formats and pulls them from your current culture (System.Threading.Thread.CurrentThread.CurrentCulture.DateTimeFormat) when you call DateTime.Parse(this.Text);
For example, the string "22/11/2009" does not match the ShortDatePattern for the United States (en-US) but it does match for France (fr-FR).
Now, you can either call DateTime.ParseExact and pass in the exact format string that you're expecting, or you can pass in an appropriate culture to DateTime.Parse to parse the date.
For example, this will parse your date correctly:
DateTime.Parse( "22/11/2009", CultureInfo.CreateSpecificCulture("fr-FR") );
Of course, you shouldn't just randomly pick France, but something appropriate to your needs.
What you need to figure out is what System.Threading.Thread.CurrentThread.CurrentCulture is set to, and if/why it differs from what you expect.

Although the above solutions are effective, you can also modify the webconfig file with the following...
<configuration>
<system.web>
<globalization culture="en-GB"/>
</system.web>
</configuration>
Ref : Datetime format different on local machine compared to production machine

You might need to specify the culture for that specific date format as in:
Thread.CurrentThread.CurrentCulture = new CultureInfo("en-GB"); //dd/MM/yyyy
this.Text="22/11/2009";
DateTime date = DateTime.Parse(this.Text);
For more details go here:
http://msdn.microsoft.com/en-us/library/5hh873ya.aspx

Based on this reference, the next approach worked for me:
// e.g. format = "dd/MM/yyyy", dateString = "10/07/2017"
var formatInfo = new DateTimeFormatInfo()
{
ShortDatePattern = format
};
date = Convert.ToDateTime(dateString, formatInfo);

After spending lot of time I have solved the problem
string strDate = PreocessDate(data);
string[] dateString = strDate.Split('/');
DateTime enter_date = Convert.ToDateTime(dateString[1]+"/"+dateString[0]+"/"+dateString[2]);

private DateTime ConvertToDateTime(string strDateTime)
{
DateTime dtFinaldate; string sDateTime;
try { dtFinaldate = Convert.ToDateTime(strDateTime); }
catch (Exception e)
{
string[] sDate = strDateTime.Split('/');
sDateTime = sDate[1] + '/' + sDate[0] + '/' + sDate[2];
dtFinaldate = Convert.ToDateTime(sDateTime);
}
return dtFinaldate;
}

use this to convert string to datetime:
Datetime DT = DateTime.ParseExact(STRDATE,"dd/MM/yyyy",System.Globalization.CultureInfo.CurrentUICulture.DateTimeFormat)

Just like someone above said you can send it as a string parameter but it must have this format: '20130121' for example and you can convert it to that format taking it directly from the control. So you'll get it for example from a textbox like:
date = datetextbox.text; // date is going to be something like: "2013-01-21 12:00:00am"
to convert it to: '20130121' you use:
date = date.Substring(6, 4) + date.Substring(3, 2) + date.Substring(0, 2);
so that SQL can convert it and put it into your database.

Worked for me below code:
DateTime date = DateTime.Parse(this.Text, CultureInfo.CreateSpecificCulture("fr-FR"));
Namespace
using System.Globalization;

You can use also
this.Text = "22112009";
DateTime newDateTime = new DateTime(Convert.ToInt32(this.Text.Substring(4, 4)), // Year
Convert.ToInt32(this.Text.Substring(2,2)), // Month
Convert.ToInt32(this.Text.Substring(0,2)));// Day

Also I noticed sometimes if your string has empty space in front or end or any other junk char attached in DateTime value then also we get this error message