级别码生成树的代码

    /**//// <summary>
    /// TreeView控件工具包
    /// </summary>
    public static class TreeViewControlUtil
    {
        /**//// <summary>
        /// 构建一颗级别树的方法
        /// <example>
        /// 调用方法:
        /// <code>
        /// TreeControlUtil.BuildTree&lt;TestNode&gt;(treeView1.Nodes[0],
        /// new TestNode[] {
        ///    new TestNode("003","TomInfo"),
        ///    new TestNode("003001","Name"),
        ///    new TestNode("003002","Age"),
        ///    new TestNode("003003","Sex"),
        ///    new TestNode("004","JaneInfo"),
        /// },
        /// "Key", "Value", 3);
        /// </code>
        /// <code>
        /// public class TestNode
        /// {
        ///     public TestNode(System.String Key, System.String Value)
        ///     {
        ///     this.Key = Key;
        ///     this.Value = Value;
        ///     }
        /// 
        ///     System.String key = System.String.Empty;
        ///     public System.String Key
        ///     {
        ///     get { return key; }
        ///     set { key = value.Trim(); }
        ///     }
        ///     System.String value = System.String.Empty;
        ///     public System.String Value
        ///     {
        ///     get { return value; }
        ///     set { this.value = value.Trim(); }
        ///     }
        /// }
        /// </code>
        /// </example>
        /// </summary>
        /// <typeparam name="T">来源数据的类型</typeparam>
        /// <param name="RootNode">根节点</param>
        /// <param name="NodeData">来源数据数组</param>
        /// <param name="CodeProperty">数据在树上的标识属性</param>
        /// <param name="TextProperty">数据在树上的文字属性</param>
        /// <param name="Length">标识级别长度</param>
        public static void BuildTree<T>(
            System.Windows.Forms.TreeNode RootNode,
            T[] NodeData,
            System.String CodeProperty,
            System.String TextProperty,
            System.Int32 Length
            )
        {

            //有效判断
            if (NodeData == null &&
                NodeData.Length <= 0 &&
                RootNode == null)
                return;

            //临时表
            System.Data.DataTable dt
                = new System.Data.DataTable();

            dt.Columns.Add(new System.Data.DataColumn("Key", typeof(String)));
            dt.Columns.Add(new System.Data.DataColumn("Value", typeof(String)));

            System.Reflection.PropertyInfo piKey
                = typeof(T).GetProperty(CodeProperty);
            System.Reflection.PropertyInfo piValue
                = typeof(T).GetProperty(TextProperty);

            foreach (T Data in NodeData)
            {
                System.Object KeyObject = piKey.GetValue(Data, null);
                System.Object ValueObject = piValue.GetValue(Data, null);
                if (KeyObject != null &&
                    ValueObject != null &&
                    KeyObject.ToString().Trim().Length > 0 &&
                    ValueObject.ToString().Trim().Length > 0)
                {
                    try
                    {
                        System.Data.DataRow dr = dt.NewRow();
                        dr["Key"] = KeyObject.ToString().Trim();
                        dr["Value"] = ValueObject.ToString().Trim();
                        dt.Rows.Add(dr);
                    }
                    catch
                    { }
                }
            }

            foreach (System.Data.DataRow dr in dt.Select(System.String.Empty, "Key ASC"))
            {
                System.Windows.Forms.TreeNode[] tnL = null;
                try
                {
                    tnL =
                        RootNode.Nodes.Find(dr["Key"].ToString().Substring(0, dr["Key"].ToString().Length - Length), true);
                }
                catch
                { }
                if (tnL != null && tnL.Length > 0)
                {
                    tnL[0].Nodes.Add(dr["Key"].ToString(), dr["Value"].ToString());
                }
                else
                {
                    RootNode.Nodes.Add(dr["Key"].ToString(), dr["Value"].ToString());
                }
            }

            RootNode.ExpandAll();

        }
    }