title: How do I check if a selected item has changed from the previously selected item?
body: <p>I have a listbox in my winform, when an item in the listbox is selected, a value is placed into a textbox in the same Form. There my many items in my listbox which when selected, i want the text box to be empty so i can pass in the new value. How do i check is if the user has clicked on something other their initial selected item? i get the currently selected item like this below:</p>
  
  <pre><code>var selectedItem = (ReportItems)listbox.selectedItem
  </code></pre>