throw new NotImplementedException();刻方法无法实现。。。。

Question

我在做一个分类树，可惜都做好了，代码是拷以前成功的一个代码，在开始运行的时候说是方法存根出现问题了，后来我设置了以后，在运行一进入分类树的界面就显示错误，代码如下，各位看看此问题因该如何解决？
namespace 医院管理系统.Model
{
    class HuaJiaDaoCategoryTreeNode : TreeNode
    {
        private HuaJiaCategory cat;        internal HuaJiaCategory Cat
        {
            get { return cat; }
            set { cat = value; }
        }        public HuaJiaDaoCategoryTreeNode(HuaJiaCategory cat):base (cat.Cname)
        {
            this.cat = cat;
        }        internal static HuaJiaDaoCategoryTreeNode searchTree()
        {
            throw new NotImplementedException();
        }
    }
}namespace 医院管理系统.Model
{
    class HuaJiaCategory
    {
        private int cid;        public int Cid
        {
            get { return cid; }
            set { cid = value; }
        }
        private string cname;        public string Cname
        {
            get { return cname; }
            set { cname = value; }
        }
        private int pid;        public int Pid
        {
            get { return pid; }
            set { pid = value; }
        }
        public HuaJiaCategory(int cid, string cname, int pid)
        {
            this.cid = cid;
            this.cname = cname;
            this.pid = pid;
        }
    }
}public static HuaJiaDaoCategoryTreeNode searchTree()
        {
            HuaJiaCategory croot = new HuaJiaCategory(0, "诊断病人", -1);
            HuaJiaDaoCategoryTreeNode root = new HuaJiaDaoCategoryTreeNode(croot);            HuaJiaDaoCategoryTreeNode cnode = null;
            HuaJiaCategory category = null;
            int cid;
            string cname;
            int pid;            try
            {
                SqlConnection conn = Connect.getConnection();
                conn.Open();
                //查询分类表中顶级分类
                string sql = string.Format("select * from 划价分类树1");
                SqlCommand command = new SqlCommand(sql, conn);
                //查询所用的数据库执行代码
                SqlDataReader reader = command.ExecuteReader();
                while (reader.Read())
                {
                    cid = int.Parse(reader[0].ToString());
                    cname = reader[1].ToString();
                    pid = int.Parse(reader[2].ToString());
                    category = new HuaJiaCategory(cid, cname, pid);
                    cnode = new HuaJiaDaoCategoryTreeNode(category);
                    root.Nodes.Add(cnode);
                    cnode.Nodes.Add("病历");
                    cnode.Nodes.Add("处方");
                    cnode.Nodes.Add("处置");
                    cnode.Nodes.Add("检查");
                    cnode.Nodes.Add("诊断");
                }
                if (conn != null)
                {
                    conn.Close();
                }
            }
            catch (Exception e)
            {
                MessageBox.Show(e.Message);            }
            return root;
        }
 public partial class HuaJiaForm : Form
    {
        MainForm mainform;
        public HuaJiaForm(MainForm mainform)
        {
            InitializeComponent();
            this.mainform = mainform;
        }        private void HuaJiaForm_Load(object sender, EventArgs e)
        {
            HuaJiaDaoCategoryTreeNode root = HuaJiaDaoCategoryTreeNode.searchTree();
            this.treeView1.Nodes.Add(root);//根据根节点构造树
        }
    }

Answer 1

HuaJiaDaoCategoryTreeNode.searchTree(); 
你这句是连到这里得嘛
        internal static HuaJiaDaoCategoryTreeNode searchTree() 
        { 
            throw new NotImplementedException(); 
        } 你中间有个searchTree();似乎不属于任何类，你代码是不是在调一调，至少也让中间这个方法
归于某个类再说，然后再把调用对准这个方法，试试。