The solution 1 given by
OriginalGriff is good.
Alternatively, using
string.Join
method and
LINQ
can be used as follows
string[] itemsAsStrings = (from p in listBox1.Items.OfType<object>()
select p.ToString()).ToArray();
object[] arrayOfItems = listBox1.Items.OfType<object>().ToArray();
string allItems = string.Join(", ",listBox1.Items.OfType<object>());
string selectedItems= string.Join(", ",listBox1.SelectedItems.OfType<object>());