private static void UpdateProviderList(CheckedListBox.ObjectCollection items, string targetServer = null)
{
if (Providers == null)
{
Providers = new System.Collections.Generic.List<string>(SystemEventEnumerator.GetEventProviders(targetServer, null, true));
}
items.Clear();
items.AddRange(Providers.ConvertAll<DropDownCheckListItem>(s => { var p = s.Split('|'); return new DropDownCheckListItem(p[1], p[0]); }).ToArray());
}