.NET (Core and Framework)

10-Jun-21 23:14

I have an ASP Net Core Web app which uses Razor pages, on one of the pages I use a datepicker as part of a data entry form, I have a problem where the date I select is somehow changing to the day before by the time it hits the database ( Postgresql ). In my controller action the date value received is correct - I'm using npgsql as the data provider - any idea what could be causing this ?

"I didn't mention the bats - he'd see them soon enough" - Hunter S Thompson - RIP

SeeSharp211-Jun-21 2:22

11-Jun-21 2:22

I have seen this before and I don't recall where it was. But what is likely happening is the value 2021-06-11 00:00:00 is getting passed but somewhere it is then getting translated into your time zone, which I am guessing is -x from UTC. And so then it becomes, for example, 2021-06-10 20:00:00, if you were on the East Coast in the US.

You'll have to keep tracking it until you find where it changes.

pkfox12-Jun-21 1:15

12-Jun-21 1:15

Hi and thanks for replying. So you have a better understanding I list out below what is happening..

The data is input and posted using a Razor page.
The Web app Controller action issues a TryUpdateModelAsync which populates an instance of my class with the form data - at this point the date in the class is correct.
I then pass my class object to an API running on my local LAN which pushes the data to a database , at this point the date in the class object has changed.
So on it's journey to the API it is somehow changing the date.
Both the Web app and the API are hosted on a Linux box.

"I didn't mention the bats - he'd see them soon enough" - Hunter S Thompson - RIP

SeeSharp214-Jun-21 2:12

14-Jun-21 2:12

pkfox wrote:
So on it's journey to the API it is somehow changing the date.

Are you using a JSON serializer? That can do it.

pkfox14-Jun-21 7:21

14-Jun-21 7:21

Yes the API uses the NewtonSoft serialiser / deserialiser - weird that the date is always a day out. But as I said in another reply - I called the API from Postman ( hard coded JSON in the body ) and it worked as expected.

"I didn't mention the bats - he'd see them soon enough" - Hunter S Thompson - RIP

SeeSharp214-Jun-21 8:02

14-Jun-21 8:02

pkfox wrote:
I called the API from Postman ( hard coded JSON in the body ) and it worked as expected.

Precisely. JSON sees 2021-06-14 00:00:00 AS UTC time and converts it for you. I don't remember how to get around it but if you google it, you should find it.

pkfox14-Jun-21 22:48

14-Jun-21 22:48

I use RestSharp in my API which I believe uses a JsonSerialiser / JsonDeserialiser - do you think this is where the problem lies ?

"I didn't mention the bats - he'd see them soon enough" - Hunter S Thompson - RIP

SeeSharp215-Jun-21 2:21

15-Jun-21 2:21

I do. I think the Json serializer is expecting the datetime to be in UTC format.

pkfox15-Jun-21 22:43

15-Jun-21 22:43

I think I've got things working. After your suggestion that it could be a serializing problem I googled and found a post written by one of the RestSharp developers regarding the use of custom serializers, he gave some sample code which I duly cut'n pasted and it seems to have done the trick. Thanks very much for pointing me in the right direction.

"I didn't mention the bats - he'd see them soon enough" - Hunter S Thompson - RIP

SeeSharp216-Jun-21 3:02

16-Jun-21 3:02

No problem. Glad you got it working.

pkfox16-Jun-21 5:42

16-Jun-21 5:42

While I have your ear - how can I set the datepicker to the date value in my model when I'm editing - I've tried the code below but it just shows a text box with the string dd-mm-yyy in until I click in it and then it pops up

@Html.TextBoxFor(m => m.DateUsed, new { @class = "datepicker", Type = "date", Value = Model.DateUsed }) -- DateUsed is my DateTime property

"I didn't mention the bats - he'd see them soon enough" - Hunter S Thompson - RIP

SeeSharp216-Jun-21 6:01

16-Jun-21 6:01

I have not used the jquery datepicker in this way but this link seems to explain how to do it, How to apply jQuery DatePicker in ASP.NET MVC in Create and Edit View - Stack Overflow[^]

Gerry Schmitz12-Jun-21 5:40

12-Jun-21 5:40

Is it a "Timestamp"?

Quote:
Note: The SQL standard requires that writing just timestamp be equivalent to timestamp without time zone, and PostgreSQL honors that behavior. (Releases prior to 7.3 treated it as timestamp with time zone.) timestamptz is accepted as an abbreviation for timestamp with time zone; this is a PostgreSQL extension.

It was only in wine that he laid down no limit for himself, but he did not allow himself to be confused by it.
― Confucian Analects: Rules of Confucius about his food

pkfox12-Jun-21 6:20

12-Jun-21 6:20

The table column is of type date

"I didn't mention the bats - he'd see them soon enough" - Hunter S Thompson - RIP

Gerry Schmitz12-Jun-21 6:25

12-Jun-21 6:25

"date" has a "one day resolution". Perhaps a (internal) rounding thing going from one representation to another.

It was only in wine that he laid down no limit for himself, but he did not allow himself to be confused by it.
― Confucian Analects: Rules of Confucius about his food

pkfox12-Jun-21 22:12

Start a process in the same way as with a double click

12-Jun-21 22:12

Hi Gerry I just called my API using postman and everything worked as expected so it's not the database.

"I didn't mention the bats - he'd see them soon enough" - Hunter S Thompson - RIP

Adrian Peters3-Jun-21 2:07

Adrian Peters

3-Jun-21 2:07

Good day,

I have the following problem:
I want to launch a specific application through a program I developed (C# .NET/C++). Unfortunately, this program cannot be started through the usual ways like Process.Start, Shell, etc, because it refuses to be started automatically. I already tried to start a .lnk file or to do the whole thing via cmd, unfortunately the program always knows that it was not started by hand. I also tried to open it via the web browser, but even there it recognizes the difference between a manual and automated start.

I am now looking for a way to start a .lnk file (this contains the parameters), but just as if I double-click on it, so that this program does not realize that it was started automatically.

I don't want to use something like AutoHotkey because I want the program to work the same on every computer. Is there any way to disguise the call so that the program doesn't notice.

I would be very grateful for any help.

Programming language and way doesn't matter to me in principle, as long as I can integrate it into my C#/C++ project by a call.

Re: Start a process in the same way as with a double click

Victor Nijegorodov3-Jun-21 3:34

Victor Nijegorodov

3-Jun-21 3:34

Could it help you: windows - executing exe using cmd or double click - Stack Overflow

Re: Start a process in the same way as with a double click

Adrian Peters3-Jun-21 4:07

Adrian Peters

3-Jun-21 4:07

No idea why this is so easy. But I really have to thank you! I have already tried it with start, but the idea to use explorer I would never have come.

It works now! Thank you very much! Laugh | :laugh:

New to UWP: Need Help Understanding UI Element Properties

RWey19-May-21 9:28

RWey

19-May-21 9:28

I've spent many years with WinForms and have concluded learning UWP is long overdue. I'm doing OK so far, but the one thing I'm having trouble finding info about is the UI Element properties. Namely, the Brush, Layout, Appearance, Common, Automation, etc. properties you see in one form or another for all UI elements in the design view.

I realize this is not a very specific question and I did search, but found nothing.

What I'm looking for is some documentation/link describing in detail all of these properties and what they have in common to the UI Elements. Understanding is key to better programming.

Thanks for any recommendations.

Regards,
R. Wey

Re: New to UWP: Need Help Understanding UI Element Properties

Gerry Schmitz23-May-21 9:40

Re: New to UWP: Need Help Understanding UI Element Properties

23-May-21 9:40

For what it's worth, you've identified the most obscure properties; even "Brush" shows up as Foreground, Background and Fill (and not as a "brush" per se) in "UI Elements".

It was only in wine that he laid down no limit for himself, but he did not allow himself to be confused by it.
― Confucian Analects: Rules of Confucius about his food

RWey25-May-21 9:39

RWey

25-May-21 9:39

Given more investigation since my original post, I understand what you're saying.

My general problem is that I never jumped on board the moment WPF came out, as Windows apps were never my true occupation. I've built numerous WinForms apps, some quite polished, for utility purposes and WinForms has served me quite well. I am now faced with "catching up" and painful as it is I feel confident I will eventually succeed.

To answer my own question, however, I've found an excellent video series on YouTube by Bob Tabor which presents a 70+ part series on UWP.

For anyone interested (newcomers like me), the first video is UWP 001 Series Introduction - YouTube[^]

You can search YouTube to easily find all in the series.

Regards,
R. Wey

Re: New to UWP: Need Help Understanding UI Element Properties

Gerry Schmitz26-May-21 10:32