protected virtual void RaisePostBackEvent (string eventArgument)
{
ValidateEvent (UniqueID, eventArgument);
string[] args = eventArgument.Split ('|');
TreeNode node = FindNodeByPos (args[1]);
if (node == null)
return;
if (args [0] == "sel")
HandleSelectEvent (node);
else if (args [0] == "ec")
HandleExpandCollapseEvent (node);
}