title: BindingContext problem
body: <p>I'm having problems with BindingContext in a .NET application. I need to populate 6 comboboxes with the same datasource but the first 3 comboboxes must be indepedent from the last 3 comboboxes.</p>
  
  <p>I coded the following:</p>
  
  <pre><code>        combo_Bancos_cheque.DataSource = bancos;
          combo_Bancos_cheque.DisplayMember = "Nombre";
          combo_Bancos_cheque.ValueMember = "IDBanco";
          combo_ctas_cheque.DataSource = bancos;
          combo_ctas_cheque.DisplayMember = "NoCuenta";
          combo_clabe_cheque.DataSource = bancos;
          combo_clabe_cheque.DisplayMember = "CLABE";
  
          combo_Bancos_dep.BindingContext = new BindingContext();
          combo_Bancos_dep.DataSource = bancos;
          combo_Bancos_dep.DisplayMember = "Nombre";
          combo_Bancos_dep.ValueMember = "IDBanco";
          combo_ctas_dep.DataSource = bancos;
          combo_ctas_dep.DisplayMember = "NoCuenta";
          combo_clabe_dep.DataSource = bancos;
          combo_clabe_dep.DisplayMember = "CLABE";
  </code></pre>
  
  <p>The first 3 comboboxes work fine, when combo_Bancos_cheque changes combo_ctas_cheque and combo_clabe_cheque also change which is the expected behaviour. Then I create a new BindingContext to unbind 4,5 &amp; 6 combobox which also use the same datasource. 
  The problem here is: when combo_Bancos_cheque value changes, combo_ctas_dep &amp; combo_clabe_dep also change but I don't want this, I need these comboboxes to change only when combo_Bancos_dep changes.</p>
  
  <p>I'm new to BindingContexts, what am I missing?</p>