title: Adding TimeZoneInfo to Combobox and setting SeletedItem baffles me
body: <p>So I am populating a combobox with all the computers time zones and then by default selecting the local time zone. I can populate the combobox but the selecting of the default item has me puzzled.</p>
  
  <pre><code>'load up the combobox with all time zones
  Dim tzCollection As ReadOnlyCollection(Of TimeZoneInfo) = TimeZoneInfo.GetSystemTimeZones()
  cboClockTmZone1.DataSource = tzCollection
  
  'the computers local time zone
  Dim myZone As TimeZoneInfo = TimeZoneInfo.Local
  
  'get the index of the local time zone in the collections
  Dim idx As Integer = tzCollection.IndexOf(myZone)
  Dim qdx As Integer = cboClockTmZone1.Items.IndexOf(myZone)
  
  'set the time zone
  'cboClockTmZone1.SelectedIndex = idx 'this works
  cboClockTmZone1.SelectedIndex = qdx 'this does not
  </code></pre>
  
  <p>So maybe my lack of understanding this but when i bind the collection to the combobox does it not get filled with TimeZoneInfo objects. In other words isn't each list item of type TimeZoneInfo? If so why doesn't the qdx assignment not work? I get back a -1 which means it couldn't find the timezone object in the combobox but it can find it in the tzCollection. I also experimented with .SelectedItem but that didn't pan out either.</p>
  
  <p>I'm just not understanding how this is supposed to work. It works now because I think there is a one-to-one mapping from tzCollection to the cbo items. But if someone can shed some light on these two methods so I can understand better, I would appreciate it.</p>