I have the following code in my C# program.
DateTime dateForButton = DateTime.Now;
dateForButton = dateForButton.AddDays(-1); // ERROR: un-representable DateTime
Whenever I run it, I get the following error:
The added or subtracted value results in an un-representable DateTime.
Parameter name: value
Iv'e never seen this error message before, and don't understand why I'm seeing it. From the answers Iv'e read so far, I'm lead to believe that I can use -1 in an add operation to subtract days, but as my question shows this is not the case for what I'm attempting to do.
DateTime dateForButton = DateTime.Now.AddDays(-1);
That error usually occurs when you try to subtract an interval from DateTime.MinValue or you want to add something to DateTime.MaxValue (or you try to instantiate a date outside this min-max interval). Are you sure you're not assigning MinValue somewhere?
You can do:
DateTime.Today.AddDays(-1)
You can use the following code:
dateForButton = dateForButton.Subtract(TimeSpan.FromDays(1));
The dateTime.AddDays(-1) does not subtract that one day from the dateTime reference. It will return a new instance, with that one day subtracted from the original reference.
DateTime dateTime = DateTime.Now;
DateTime otherDateTime = dateTime.AddDays(-1);
Instead of directly decreasing number of days from the date object directly, first get date value then subtract days. See below example:
DateTime SevenDaysFromEndDate = someDate.Value.AddDays(-1);
Here, someDate is a variable of type DateTime.
The object (i.e. destination variable) for the AddDays method can't be the same as the source.
Instead of:
DateTime today = DateTime.Today;
today.AddDays(-7);
Try this instead:
DateTime today = DateTime.Today;
DateTime sevenDaysEarlier = today.AddDays(-7);
I've had issues using AddDays(-1).
My solution is TimeSpan.
DateTime.Now - TimeSpan.FromDays(1);
Using AddDays(-1) worked for me until I tried to cross months. When I tried to subtract 2 days from 2017-01-01 the result was 2016-00-30. It could not handle the month change correctly (though the year seemed to be fine).
I used date = Convert.ToDateTime(date).Subtract(TimeSpan.FromDays(2)).ToString("yyyy-mm-dd");
and have no issues.
Related
I have been trying to set a time limit for a certain form to not function past a specified date in a month, but I have been unsuccessful so far.
I am working with a low-code windows interface software that does the majority of the actual coding in the background but since it has some limitations I need to code this Date limit in myself.
The best thing I reached after looking around was this:
DateTime temp = new DateTime(DateTime.Now.Year, DateTime.Now.Month, 15);
And I would add a rule in the program that the date shouldn't be higher than the above.
But for some reason it doesn't work giving me an "; expected" error (in line 1 char 29).
This will only open the specified form up to and including the 15th of the month:
if (DateTime.Now.Day <= 15)
{
myForm.Show();
}
You can obviously change the operator and/or value to change the way it works. The important point is the Day property of the DateTime value representing the current date.
you can use the below code. you have to use AddDays method.
DateTime now = DateTime.Now;
DateTime pastTime = now.AddDays(-15);
DateTime futureTime = now.AddDays(15);
It will give you backdate if you provide a negative value.
you also have a typo in your code, the correct DataType is DateTime.
you can comparisons as you have for int, and doubles.
if(now < pastTime)
{
}
The Error:
"; expected" error (in line 1 char 29).
You're missing a ending semi-colon, probably in a line above or below.
Tip: try to name variables well with meaning especially in anything-but-code (ABC) environments:
DateTime avoidReservedKeyWords = new DateTime(DateTime.Now.Year, DateTime.Now.Month, 15);
I want to get yesterday's date with the time of my choice ( customized time ) and store it in a variable in windows forms C#.
For example: if today's date/Time was 2010-09-25 10:05:03 I want to get the date of the previous day ( 2010-09-24 ) and change the time to 14:30:00 then store it in a variable.
The following codes might help:
DateTime.Now; // it gives you today's Date and current Time
DateTime.Today.AddHours(14:5); // it gives you the current date with customized time (`14:30:00`).
DateTime.Now.AddDays(-1); // it gives you the previous day
Please help me how to achieve this. Thank you.
You can combine the statements like this
var dateTime = DateTime.Now.AddDays(-1).Date.AddHours(14.5);
But remember DateTime objects are immutable so every time you modify a DateTime object you have to assign it to a variable.
You can get DateTime.Now.Date to cut time off, and then add time components.
var result = DateTime.Now.Date.AddDays(-1)
.AddHours(14)
.AddMinutes(30)
.AddSeconds(21);
It will result in 14:30:21 of the previous day.
I have already seen this.
I am going to get only Date from a DateTime variable and in this way I used this code:
DateTime Start = GetaDateTime();
String Day = Start.ToString("yyyy/MM/dd");
DateTime d = Convert.ToDateTime(Day);
But when I use d.Date it gives me '2014-08-23 12:00 AM'
Actually I should not get 12:00AM any more????
Actually I should not get 12:00AM any more????
Why not? A DateTime has no notion of whether it's meant to be a date or a date and time, or any sort of string formatting. It's just a point in time (and not even quite that, given the odd Kind part of it).
Note that a simpler way of getting a DateTime which is the same as another but at midnight is just to use Date to start with:
DateTime start = Foo();
DateTime date = start.Date;
No need for formatting and then parsing.
There's no .NET type representing just a date. For that, you'll want something like my Noda Time project, which has a rather richer set of date/time types to play with.
Sorry if this seems as a stupid question, but I cannot find an answer anywhere and I am a bit of a newbie. DateTime shows to be what I surmised as the Min Date. For instance:
DateTime updatedDate = new DateTime();
outItem.AddDate = updatedDate.ToLongDateString();
The output comes out to January 01, 0001. I've tried many variations of this with similar results. What am I doing wrong?
It depends on what you mean by "wrong". new DateTime() does indeed have the same value as DateTime.MinValue. If you want the current time, you should use:
DateTime updatedDate = DateTime.Now;
or
DateTime updatedDate = DateTime.UtcNow;
(The first gives you the local time, the second gives you the universal time. DateTime is somewhat messed up when it comes to the local/universal divide.)
If you're looking to get the current date, use DateTime.Now. You're creating a new instance of the date class, and the min value is its default value.
DateTime updatedDate = DateTime.Now;
outItem.AddDate = updatedDate.ToLongDateString();
EDIT: Actually, you can shorten your code by just doing this:
outItem.AddDate = DateTime.Now.ToLongDateString();
Jon Skeet says correct, and I have some to add.
The "wrong" depends on what time you want to get.
The DateTime is a struct, and the the default contructor of a struct
always initializes all fields to their zero for numeric type and null
for reference type.
so if you want to get the current local date and time, you can call static property DateTime.Now.
var curDateTime = DateTime.Now;
if you want to get UTC time.
var utcDateTime = DateTime.UtcNow;
Note: the DateTime.UtcNow get the current date and time, but instead of using local time zone, it uses UTC time instead.
You can reference the link as below.
http://blackrabbitcoder.net/archive/2010/11/18/c.net-little-wonders-datetime-is-packed-with-goodies.aspx
can someone tell me how to conver DatePicker value to DateTime value...
I have this variables:
DateTime now = DateTime.Now;
DatePicker rd = rd_datePicker;
I would like to get difference in days betwen this two dates, can you help me with this too?
Have you tried using DatePicker.SelectedDate?
Once you've got the two DateTime values (you may want to use DateTime.Today instead of DateTime.Now) you can subtract one from the other to get a TimeSpan, and then use TimeSpan.TotalDays to find out the number of days in the period.
(As DateTime is effectively a "local" representation, you don't need to worry about time zones or variable day lengths in this particular case. Date and time arithmetic in general is rather tricky...)
DatePicker dp = new DatePicker();
DateTime dt=new DateTime();
dp.Text = dt.Date.ToString("yyyy/MM/dd");