title: how to set datamember for bindingsource when using Entity Framework
body: <p>I am trying to learn EF and databinding with winforms. I have 2 bindingsources. For the first one "bsa" I've set the datasource and did not set the datamember. For the second bindingsource "bsb" I've set the datasource as "bsa" and trying to set datamember property as per below. I am getting an error saying "DataMember property 'Contact.Addresses' cannot be found on the DataSource.".</p>
  
  <p>private void Form1_Load(object sender, EventArgs e)</p>
  
  <pre><code>  {
          var contactList = context.Customers.Include("Contact")
              .Include("PrimaryDestination")
              .Include("CustomerType")
              .Include("PrimaryActivity")
              .Include("Reservations").ToList();
  
          bsa.DataSource = contactList;
  
          dataGridView1.DataSource = bsa;
          dataGridView1.AutoGenerateColumns = true;
  
          bsb.DataSource = bsa;
  </code></pre>
  
  <p>//Customer has contact navigation property and contact has addresses navigation property</p>
  
  <pre><code>        bsb.DataMember = ("Contact.Addresses");        
          dataGridView2.DataSource = bsb;
  
          dataGridView2.AutoGenerateColumns = true;
      }
  </code></pre>
  
  <p>Can I actually set the datamember of the second bindingsource "bsb" without setting the datamember for the first bindingsource "bsa"?</p>