How prevent duplicate items listView C#

Question

I am using Windows Forms. With this code I add items to listView from comboBox.

ListViewItem lvi = new ListViewItem();         


        

Answer 1

String csVal = Value;
ListViewItem csItem = new ListViewItem(csVal);
if (!listViewABC.Items.ContainsKey(csVal))
{
    csItem.Name = csVal;
    listViewABC.Items.Add(csItem );
}