title: show/hide another combobox, with the help of combobox items
body: <p>I have a little problem that i'm creating a simple search application which have a TEXT box and some combo boxes and radio buttons and a search button.
  radio button names "Videos", "Audios", "Pics" etc..
  when radiobutton of video is selected, a combobox is appear having options "YouTube", "Metacafe" etc
  I want that when i click "Metecafe" item in combobox of video, an other combo box appear having items Like "Entertainment", "How To", "+18" etc(categories of video search).
  so "HOW TO SHOW/HIDE AN OTHER COBOBOX WITH THE HELP OF A COMBOBOX ITEM"
  hope you have understood my problem.
  <a href="http://goo.gl/FLoJO" rel="nofollow">screen shoot</a>
   i don't know it is possible or not becux i'm beginner in VB
  my English is not so good so please see below code:)</p>
  
  <pre><code>if combobox1.SelectedItem = "PAKISTAN" Then
      combobox2.Visible = True
  End if
  
  if combobox1.SelectedItem = "INDIA" Then
      combobox3.visible = true
      combobox2.visible = false
   End if
  </code></pre>
  
  <p>Obviously this code is wrong, this is a example that what i want to do
  Thanks to all in advance..</p>
  
  <p>NOTE:
       i have try this codes but its not working..</p>
  
  <pre><code>if ComboBox1.Items(ComboBox1.SelectedIndex).ToString() = "PAKISTAN" Then
  
      ComboBox2.Visible = True
  
  End if
  </code></pre>
  
  <p>sorry for spell and grammatical mistakes:(</p>