Winforms中的数据绑定

Question

I have a data entry Winforms App in VS2010. Along with an Entity Data Model (.edmx) that is connected to a SQL Compact Database. In this database I have a table Ticket that I am trying to make an insert into.

On my form, I have all my controls DataBindings property setup and pointing to the correct fields in the database.

I am trying to take the values from the controls on the form and add one non-databound field and save the ticket.

Here is my code:

private void btnSave_Click(object sender, EventArgs e)
    {
                this.TS = new TicketService();
                Ticket t = (Ticket)ticketBindingSource.DataSource;
                t.DateEntered = Datetime.Now;
                TS.SaveTicket(t);
    }

I am getting an error with Converting the TicketBindingSource to the Ticket Object.

Anyone know how to do this conversion?

Thanks

Edit: I am not sure if I was clear enough on my issue, I do not believe this is uncommon. All I am trying to do is take the data from my databound controls, place it into a variable, add a non-databound data (egtDateEntered = DateTime.Now like in the example above) and then Save the data to the database.

I have done this in VB.Net, but VB.Net does this conversion from the DataSource to the Variable automatically. Here is the VB.Net code:

            Dim t = ticketBindingSource.DataSource
            t.DateEntered = DateTime.Now()
            TicketService.SaveTicket(t)

C# does not do this automatically, it throws an error.

Answer 1

I'm not sure about your problem but these two lines do not make sense:

Ticket t = new Ticket();
t = (Ticket)ticketBindingSource.DataSource;

You create a Ticket and assign it to t.

Then, you immediately re-assign t to something else. The Ticket you created is never used and gets garbage collected.

Answer 2

I don't know what do you want exactly, but this is a very good example:

Insert, Update and Delete using Entity Framework

I hope help you.

Happy code !