title: Check if an item is already exist in listbox1
body: <p>In form1 I have two listboxs: listbox1, listbox2; loadbutton and savebutton </p>
  
  <p>This code will write listbox1.selecteditem into a txt file and loadbutton will load the info. </p>
  
  <p>But in listbox2 I want loadbutton to check if that item already exist in 
  listbox2, if not write selected item from listbox1 and if that item already exist in listbox2 then do not save it (msg"this item is already exist in listbox2")</p>
  
  <p>This is not working </p>
  
  <pre><code>Dim wri As New IO.StreamWriter("e:\test.txt", True)
  If ListBox2.ToString.Contains(ListBox1.Items.Item) Then ' or ListBox1.SelectedItem ? ' not work 
      MsgBox("this item is already in listbox2")
  Else
      wri.WriteLine(ListBox1.SelectedItem, True)
  End If
  wri.Close()
  </code></pre>