utc date time

sophia · February 24th, 2012, 12:53 PM

Hello Imar,

While storing review I was thinking that why use always system date time using getdate() and not the utc date. For this I changed default value to getutcdate() in both fields CreateDateTime and UpdateDateTime in Reviews table and updated the edmx file, and removed the lines which explicitly stores the date time for review.

Review myReview;
if (_id == -1) // Insert new item
{
myReview = new Review();
//myReview.CreateDateTime = DateTime.Now;
//myReview.UpdateDateTime = myReview.CreateDateTime;
myEntities.AddToReviews(myReview);
}

But it was giving error that datetime2 type value can not be converted into datetime type value. So I changed datatype of both date time field to datetime2(7) and it is working well now.

The only problem is that it is storing default date time value 1/1/0001 12:00 AM and not the real utc date. Please tell me how to store real utc date values

Thanks

irProject · February 25th, 2012, 03:39 AM

use UtcNow instead of Now:

Code:

if (_id == -1) // Insert new item
{
myReview = new Review();
myReview.CreateDateTime = DateTime.UtcNow;
myReview.UpdateDateTime = myReview.CreateDateTime;
myEntities.AddToReviews(myReview);
}

datetime2 type is used to store datetime values with no limitation of range values. for example in Hijri date we use 1391/12/05 today instead of 2012/Mar/24 so in earlier versions we could not store date values and we was forced to convert our date values to Gregorian dates. but now there is no limitation with datetime2.

sophia · February 25th, 2012, 09:03 AM

Quote:

use UtcNow instead of Now:

I'm aware of this fact, but I do not want to set the date in code behind file. Any other method?

Thanks

sophia · February 26th, 2012, 11:44 AM

Please someone help me...

irProject · February 28th, 2012, 11:46 AM

Hi there

GetUtcDate() in sql returns the UtcTime. it works fine as it should. but I think there are some problems with edmx update. I've faced some problems with edmx updating, and I was forced to reCreate the edmx file.

sophia · February 28th, 2012, 02:07 PM

Hi Reza,
I did not delete and recreated edmx file, but yes deleted the corresponding table, saved edmx and then added again that table and saved edmx but it did not work.

How this problem can be solved?
Thanks

irProject · February 29th, 2012, 04:07 AM

Hi there
I think CreateDateTime and UpdateDateTime fields of your table are not nullable. so when Entity Framework wants to set the values, uses it's .Net default values (new DateTime()). Try to set these two fields as nullable, set default value to GetUtcDate(), update edmx file and then test below codes

Code:

if (_id == -1) // Insert new item
{
myReview = new Review();
myEntities.AddToReviews(myReview);
}

sophia · February 29th, 2012, 05:24 AM

No Luck,
Null is being stored in table

sophia · March 1st, 2012, 02:36 AM

Hi Imar, Kindly say something on this topic.

Imar · March 1st, 2012, 02:37 AM

Does it work when you add a record in the table directly?

I would add a constructor to the class and set the value from there in code.....

Imar