title: How can I bind to an Invoke operation on a DomainService?
body: <p>I'm tinkering with RIA Services and I've created a DomainService and I'm able to bind that to grids/dataforms and the like... but for the life of me I can't see how I can call custom methods on that DomainService. I've created a method like this:</p>
  
  <pre><code>[Invoke]
  public IEnumerable&lt;string&gt; GetCities()
  {
      return new List&lt;string&gt;() { "some city" };
  }
  </code></pre>
  
  <p>I want to be able to bind the items collection of a combobox to that method (one-way).</p>
  
  <p>In the silverlight page, there is a <code>peopleDomainService</code> object that is created as a resource when adding controls to the page that is used for binding. But nowhere on it can I find any of my custom methods.</p>