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asp.netgridviewtimezonelinqdatasource

How to modify Bind("MyValue") in asp.net

I'm having headache with Time values and multiple time zones. I'm storing new DateTime values in UTC time, but I face problem when I try to modify them using LinqDataSource and GridView.

I can easily show correct time in

<ItemTemplate>
    <asp:Label ID="Label1" runat="server" Text='<%# TimeManager.ToLocalTime((DateTime)Eval("OrderDate")) %>' />
</ItemTemplate>

Currently this will add 1 hour to UTC time stored in DB.

However, binding back to source is not easy. Bind("OrderDate") cannot be modified like TimeManager.ToGlobalTime((DateTime)Bind("OrderDate")).

I was thinking of using OnUpdating event of LinqDataSource to update value to global time, but what if user modified other fields and not date field? Every time he updates record time value would be smaller for one hour.

Comparing old and new values also is not great because user can modify date portion of datetime and not time, which is influenced by time zones?

If I had way to show local time in gridview's all states then I could easily use OnUpdating of LinqDataSource.

Please share your thoughts...

Solution

  • Have you considered making the change to your model? Let's assume that the name of the object you are binding to is CustomerOrder. You could add the following class to your project (in the same namespace as your Linq objects):

    public partial class CustomerOrder
{
    public DateTime LocalOrderDate
    {
        get { return TimeManager.ToLocalTime(OrderDate); }
        set { OrderDate = TimeManager.ToUTCTime(value); }
    }
}

    Now instead of binding to OrderDate, bind to LocalOrderDate. This will automatically make the UTC / Local Time conversion to the OrderDate.

    (Note: I'm assuming you have TimeManager.ToLocalTime() and TimeManager. ToUTCTime() properly defined)