JABVIR

if (txt_Search.Text != "")
        {
            foreach (ListViewItem item in listView1.Items)
            {
                if (item.Text.ToLower().Contains(txt_Search.Text.ToLower()))
                {
                    item.Selected = true;
                }
                else
                {
                    listView1.Items.Remove(item);
                }

            }
            if (listView1.SelectedItems.Count == 1)
            {
                listView1.Focus();
            }
        }
        else
        {
            LoadContacts();
            RefreshAll();
        }