# CSLA.Net:Step-by-Step – Using the BindingNavigator

I was recently asked how to use the BindingNavigator to scroll through a list of objects. It is actually a very simple process, and here’s how:

I’m using the same Northwind BO Library as with the previous posts. We have a Customer object, and the table design looks something like this:

[![image](http://www.mythicalmanmoth.com/wp-content/uploads/2009/10/image-thumb9.png "image")](http://www.mythicalmanmoth.com/wp-content/uploads/2009/10/image9.png)

Right, next create a new class called Customers. This class will inherit from EditableRootListBase . You can paste the following into the class:

 \_
Public Class Customers
Inherits EditableRootListBase(Of Customer)
#Region " Business Methods "
Protected Overrides Function AddNewCore() As Object
Dim item As Customer = Customer.NewCustomer
Add(item)
Return item
End Function
#End Region
#Region " Factory Methods "
Public Shared Function GetList() As Customers
Return DataPortal.Fetch(Of Customers)()
End Function
Private Sub New()
Me.AllowEdit = True
Me.AllowNew = True
Me.AllowRemove = True
End Sub
#End Region
#Region " Data Access "
Private Overloads Sub DataPortal\_Fetch()
Me.RaiseListChangedEvents = False
Using sqlconn As New SqlConnection(Database.NorthwindConnection)
sqlconn.Open()
Using cm As SqlCommand = sqlconn.CreateCommand
cm.CommandType = CommandType.Text
cm.CommandText = "SELECT \* FROM Customers WITH (NOLOCK)"
Using dr As New SafeDataReader(cm.ExecuteReader())
While dr.Read
Add(Customer.GetCustomer(dr.GetInt32("CustomerID")))
End While
dr.Close()
End Using
End Using
sqlconn.Close()
End Using
Me.RaiseListChangedEvents = True
End Sub
#End Region
End Class 

Compile your project and add a new form. Drag the Customers object from the Data Sources window to your newly created form. It should automatically add a BindingNavigator and a Datagridview to your form. Go ahead and delete the grid.

Next, drag the CustomerTextID, CompanyName, ContactName fields onto your form. Your form should look something like this:

[![image_3](http://www.mythicalmanmoth.com/wp-content/uploads/2009/10/image-3-thumb1.png "image_3")](http://www.mythicalmanmoth.com/wp-content/uploads/2009/10/image-31.png)

Select the Save button on the BindingNavigator and set it’s Enabled property to True. Switch to Code view and add the following declaration:

Dim \_cust As Customer

Next, add the following code to your form’s Load Event:

Private Sub Form1\_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
CustomersBindingSource.DataSource = Customers.GetList
End Sub 

Now, we need to handle the BindingNavigator’s Save event. You do not need to worry about the AddNew or Delete Events, the business object handles those for you.

Add the following code to the BindingSource’s PositionChanged event:

Private Sub CustomersBindingSource\_PositionChanged(ByVal sender As Object, ByVal e As System.EventArgs) \_
Handles CustomersBindingSource.PositionChanged
\_cust = CType(CustomersBindingSource.Current, Customer)
End Sub 

Finally, add the following to the Save button’s click event:

Private Sub CustomersBindingNavigatorSaveItem\_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) \_
Handles CustomersBindingNavigatorSaveItem.Click
\_cust.ApplyEdit()
\_cust.Save(True)
End Sub 

Press F5 and see your handy work, it should look something like this:

[![image_4](http://www.mythicalmanmoth.com/wp-content/uploads/2009/10/image-4-thumb1.png "image_4")](http://www.mythicalmanmoth.com/wp-content/uploads/2009/10/image-41.png) 

There you go, a quick and neat way to use the BindingNavigator with CSLA objects. Until next time, keep coding…