异常:未将对象引用设置到对象的实例
int iCount = 0;
//设置当前结点
for (iCount = 0; iCount < regionTree.SelectedNode.Nodes.Count; iCount++)
{
if (regionTree.SelectedNode.Nodes[iCount].Tag.ToString() == currentLabel.Tag.ToString())
{
regionTree.SelectedNode = regionTree.SelectedNode.Nodes[iCount];
}
}