title: How to update BindingSource with new instance of BindingList
body: <p>So I've got the existing code which works just fine when using the BindingList -> BindingSource -> Windows Control approach:</p>
  
  <pre><code>_items.Clear();
  foreach (Item item in GetItems())
  {
     _items.Add(item);
  }
  </code></pre>
  
  <p>Where _items is module level instance of BindingList.</p>
  
  <p>The above code works as it should, in that the grid control I'm using correctly displays the items after they have been added each time.</p>
  
  <p>However, I'm concerned about performance, specifically, having to iterate over each of the items again.  I would much prefer code like this:</p>
  
  <pre><code>_items = new BindingList&lt;Item&gt;(GetItems());
  </code></pre>
  
  <p>But it's not updating the grid with the new items as did the previously mentioned block of code.  What am I missing?</p>