title: Change event on select with knockout binding, how can I know if it is a real change?
body: <p>I am building a permissions UI, I have a list of permissions with a select list next to each permission. The permissions are represented by an observable array of objects which are bound to a select list:</p>
  
  <pre><code>&lt;div data-bind="foreach: permissions"&gt;
       &lt;div class="permission_row"&gt;
            &lt;span data-bind="text: name"&gt;&lt;/span&gt;
            &lt;select data-bind="value: level, event:{ change: $parent.permissionChanged}"&gt;
                     &lt;option value="0"&gt;&lt;/option&gt;
                     &lt;option value="1"&gt;R&lt;/option&gt;
                     &lt;option value="2"&gt;RW&lt;/option&gt;
             &lt;/select&gt;
        &lt;/div&gt;
   &lt;/div&gt;
  </code></pre>
  
  <p>Now the problem is this: the change event gets raised when the UI is just populating for the first time. I call my ajax function, get the permissions list and then the event get raised for each of the permission items. This is really not the behavior I want. I want it to be raised <strong>only when a user really picks out a new value for the permission in the select list</strong>, how can I do that?</p>