title: Getting index for multiple selected item in ListBox in c#
body: <p>I have two ListBoxes. First <code>ListBox</code> items are list of "Products". and second <code>ListBox</code> items are list of "Item in Product" so When user click the item in first(Product) Listbox The second <code>ListBox</code> will show the list of items in selected Products.</p>
  
  <p>eg:</p>
  
  <pre><code>Products     Items in Proucts
    AA*                 1
    BB                  2
    CC                  3   
  </code></pre>
  
  <p>in example above current user selected AA products. And 1,2,3 are the items in product AA.</p>
  
  <p>For the current program,i've done. User <strong>only can select One "Products" at a time</strong>. Then i want to <strong>change to multipleselected.</strong> So i want to get index number for each product that user selects, then i can retrieve data from database to get "Items In Products" for all selected products.</p>
  
  <pre><code>if (productsListBox.SelectedItmes.Count &gt;= 0)
  {
   // please provide me coding here to get index number for each selected items in   productListBox.
  }
  </code></pre>