title: Given two Arrays - contacts() & contactsSelected() - How to match the two?
body: <p>I have two arrays (contacts &amp; contactsSelected)  both with the following type of structure:</p>
  
  <pre><code>{
      id: 1,
      name: bob
  },
  {
      id: 213,
      name: Rob
  }
  </code></pre>
  
  <p>I'm using KnockoutJS. How Can I iterate over contacts() and for each row, determine if that row's ID is contained in the contactsSelected array? In KnockoutJS I have something like this:</p>
  
  <pre><code>userCardModel.contactsToShow = ko.dependentObservable(function () {      
  
          return ko.utils.arrayFilter(this.contacts(), function(contact) {
              return /////////////// LOGIC GOES HERE TO See if this contact.id() is contained in the contactsSelected() array
          });
  
  
  }, userCardModel);
  </code></pre>
  
  <p>Thanks</p>