title: Clearing ListBox value (not listBox items)
body: <p>Any idea how can I clear only data calculated by "Calculate" button (my variable value) and leave the text in my listBox unchanged. 
  So that's the display data of my listBox:</p>
  
  <pre><code>listBox1.Items[0] = listBox1.Items[0].ToString() + "  " + financeRequired.ToString();
  </code></pre>
  
  <p>that displays like that in my listBox:
  users finance required: $2000</p>
  
  <p>Tried using: <code>listBox1.Items[0] = ""; and listbox1.Items.Clear();</code> but that is just clearing the whole listBox and I need the text: "users finance required:" I have defined in the listbox (listBox1.Items[0] = listBox1.Items[0].ToString()) to remain visible and only value $2000 (financeRequired.ToString()) to be cleared so new calculation is possible.</p>
  
  <p>Thanks in advance for any suggestions and sorry for looooong story ;)</p>