connect to sql server

[ppl1]

what is wrong in my code? i cant see the records of the dataBase

  If (Not Page.IsPostBack) Then
            Dim con As SqlConnection = New SqlConnection  ("Server=localhost;Database = Northwind;Integrated Security = SSPI;")

            Dim cmd As SqlCommand = New SqlCommand("select * from Customers", con)
            cmd.Connection.Open()
            Dim reader As SqlDataReader
            reader = cmd.ExecuteReader()
            datagrid1.DataSource = reader
            datagrid1.DataBind()

            cmd.Connection.Close()
                 End If

thanks in advanced