Two way binding using Silverlight and WCF Service

Question

To simplify the question, I have a single textbox control which I want to apply two way binding. I have an object class named Customer for example on the server side, the silverlight application is obviously a separate project.

public class Customer
{
    public string Name{ get; set; }
}

In the WCF Service I have query which populates the customer name, and returns a list of type Customer.

List<Customer> data = new List<Customer>();

On the client side I then have this bound to the textbox control:

<TextBox Canvas.Left="345" Canvas.Top="12" Height="23" Name="tb_customer" Width="120" Text="{Binding Path=Name}" />

List<ServiceReference.Customer> data = e.Result;
tb_customer.DataContext = data[0];

This is working fine, and is binding the customer name to the textbox control. But my question is, when I change the value on the client side how do I go about sending the modified customer name back to the data source, in this case a table named customers in sqlserver. Would I need to implement INotifiyPropertyChanged on the customer class? But obviously the customer class is sitting on the server side, so do I need to create a local instance of the customer class on the client side, and upload these changes via the wcf service back to the server?

Answer 1

Set the Textbox up like this:

<TextBox Canvas.Left="345" Canvas.Top="12" Height="23" Name="tb_customer" Width="120" Text="{Binding Path=Name, Mode=TwoWay}" />

With this setup, changes made to the value of the textbox will automatically update the state of the object , locally. You will then have to commit the changes back to the datastore. If you are using an ORM such as Entity Framework, that's easy- just call SubmitChanges() on your context and you're done. If you're not using an ORM, you'll have to handle the update manually.