Web Application Time Zone Issue

Question

We have a ASP.Net 2.0 web application up and running with the server in the Midwest (Eastern Standard Time). At this moment all of our customers are in the same time zone as the server. We are bringing another server online in Arizona (Mountain Standard Time).

We are storing all our times in a SQL 2005 database via C# codebehind DateTime.UtcNow.

During testing we encountered some time zone conversion issues. Our problem is that in the web browser our times are displaying the Mountain Standard Time instead of the time zone we are testing from which is Eastern Standard Time.

When we enter new information it gets stored as UTC in the database, but when we go to view that info in the browser it is displaying the Mountain Standard Time. Below is the code which takes the UTC value from the database and displays it in the browser.

lblUpdatedDate.Text = Convert.ToDateTime(dr["UpdatedDate"]).ToLocalTime().ToString();

The above code returns Mountain Standard Time where the server is, not Eastern Standard Time where the browser is running from. How do we get the time to display where the user is?

Answer 1

I had the same issue. We sold our application to a user that was in a different time zone than the web server. We did not store any time information in UTC, but it was actually working correctly. Time displayed in the server's time zone was displaying exactly 3 hours behind. All we had to do was add a time zone drop down so they could select their time zone for the entire site (since the only users of the application would be in their time zone). We saved this setting and then inserted a function to take all datetime displays and convert from one time zone to the other using the TimeZoneInfo namespace. It works perfectly.

Answer 2

To local time will always on the server side convert to the physical location. You have a few options.

1. Store the offset value from UTC to the Users, keep times in UTC
2. Do the conversion client side via JS (Not elegant, nor appropriate, In my opinion)
3. Look at some MSDN recommendations and the Timezone namespace