具有树结构的表datatable生成树结构的json字符串，前台生成树

具有树结构的表datatable生成树结构的json字符串，前台生成树

1.实现效果

2.代码

 public partial class WebForm1 : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {

        }

        [WebMethod]
        public static string GetJsonTree()
        {
            DataTable dtLevels = GetData();         
            List<string> l = new List<string> { };
            string s = TableToEasyUITreeJson(dtLevels, 0, l);
            return "{"nodes":[" + s + "]}";
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="dt"></param>
        /// <param name="parentID"></param>
        /// <param name="parentNodes"></param>
        /// <returns></returns>
        public static string TableToEasyUITreeJson(DataTable dt, int parentID, List<string> parentNodes)
        {
            try
            {
                StringBuilder sb = new StringBuilder();
                DataTable dt_new = new DataTable();
                DataRow[] drs = null;
                if (parentID == 0)
                {
                    dt_new = dt.DefaultView.ToTable(true, dt.Columns[parentID].ColumnName);
                    drs = dt_new.Select();
                }
                else
                {
                    DataTable dtDdistinctNodes = dt.DefaultView.ToTable(true, dt.Columns[parentID].ColumnName);

                    string selectString = "";
                    for (int i = 0; i < parentNodes.Count; i++)
                    {
                        selectString += "" + dt.Columns[i].ColumnName + " = '" + parentNodes[i] + "' and ";
                    }

                    for (int i = dtDdistinctNodes.Rows.Count - 1; i >= 0; i--)
                    {
                        string queryString = selectString + dt.Columns[parentID].ColumnName + " = '" + dtDdistinctNodes.Rows[i][0] + "'";

                        drs = dt.Select(queryString);
                        if (drs.Length < 1)
                        {
                            dtDdistinctNodes.Rows.Remove(dtDdistinctNodes.Rows[i]);
                        }
                    }
                    drs = dtDdistinctNodes.Select();

                }

                if (drs.Length < 1)
                    return "";

                foreach (DataRow dr in drs)
                {
                    sb.Append("{");
                    sb.AppendFormat("text:"{0}",", dr[dt.Columns[parentID].ColumnName].ToString());

                    if (dt.Columns.Count > parentID + 1)
                    {
                        if (parentID == 0)
                        {
                            parentNodes.Clear();
                        }

                        parentNodes.Add(dr[0].ToString());
                        sb.AppendFormat("nodes:[{0}]", TableToEasyUITreeJson(dt, parentID + 1, parentNodes));
                        parentNodes.Remove(dr[0].ToString());
                    }

                    sb.Append("},");
                }
                return sb.ToString();
            }
            catch (Exception ex)
            {

                throw ex;
            }

        }

        public static  DataTable GetData()
        {
            DataTable dt = new DataTable();
            DataColumn dc = new DataColumn();
            dc.ColumnName = "a";
            dc.DataType = typeof(String);
            dt.Columns.Add(dc);
            dc = new DataColumn();
            dc.ColumnName = "b";
            dc.DataType = typeof(String);
            dt.Columns.Add(dc);
            dc = new DataColumn();
            dc.ColumnName = "c";
            dc.DataType = typeof(String);
            dt.Columns.Add(dc);

            DataRow dr = dt.NewRow();
            dr["a"] = "西北";
            dr["b"] = "陕西";
            dr["c"] = "西安";
            dt.Rows.Add(dr);

            dr = dt.NewRow();
            dr["a"] = "东北";
            dr["b"] = "吉林";
            dr["c"] = "长春";
            dt.Rows.Add(dr);

            dr = dt.NewRow();
            dr["a"] = "西南";
            dr["b"] = "山东";
            dr["c"] = "烟台";
            dt.Rows.Add(dr);

            dr = dt.NewRow();
            dr["a"] = "西北";
            dr["b"] = "甘肃";
            dr["c"] = "天水";
            dt.Rows.Add(dr);
            dr = dt.NewRow();
            dr["a"] = "西北";
            dr["b"] = "甘肃";
            dr["c"] = "aaa";
            dt.Rows.Add(dr);
            dr = dt.NewRow();
            dr["a"] = "西北";
            dr["b"] = "陕西";
            dr["c"] = "长安";
            dt.Rows.Add(dr);
            dr = dt.NewRow();
            dr["a"] = "西北";
            dr["b"] = "陕西";
            dr["c"] = "长安";
            dt.Rows.Add(dr);
            dr = dt.NewRow();
            dr["a"] = "东北";
            dr["b"] = "哈尔冰";
            dr["c"] = "詹姆斯";
            dt.Rows.Add(dr);
            return dt;

        }


    }

　　

<head runat="server">
     <!-- Add references to dependencies from the Wijmo CDN. The ones below may not be the most recent; please reference the latest dependencies from the Wijmo CDN at http://wijmo.com/downloads/#wijmo-cdn. -->
    <!--jQuery References-->
    <script src="http://code.jquery.com/jquery-1.9.1.min.js" type="text/javascript"></script>
    <script src="http://code.jquery.com/ui/1.10.1/jquery-ui.min.js" type="text/javascript"></script>

    <!--Theme-->
    <link href="http://cdn.wijmo.com/themes/rocket/jquery-wijmo.css" rel="stylesheet" type="text/css" />

    <!--Wijmo Widgets CSS-->
    <link href="http://cdn.wijmo.com/jquery.wijmo-pro.all.3.20131.1.min.css" rel="stylesheet" type="text/css" />

    <!--Wijmo Widgets JavaScript-->
    <script src="http://cdn.wijmo.com/jquery.wijmo-open.all.3.20131.1.min.js" type="text/javascript"></script>
    <script src="http://cdn.wijmo.com/jquery.wijmo-pro.all.3.20131.1.min.js" type="text/javascript"></script>
    <script src="../Scripts/CatalogueDefinition.js" type="text/javascript"></script>
    <title></title>
    <script>
        $(document).ready(function () {
            $.ajax({
                cache: false,
                async: false,
                type: "POST",
                url: "WebForm1.aspx/GetJsonTree",
                contentType: "application/json; charset=utf-8",
                dataType: "json",
                success: function (results) {
                    var strJSON = results.d; //得到的JSON
                    var data = eval("(" + strJSON + ")"); //转换后的JSON对象
                    var opts = {
                        showCheckBoxes: true,
                        nodes: data.nodes

                    };
                    $("#tree").html("");
                    $("#tree").wijtree(opts);
                }
            })
        });

        $(document).ready(
            
        );
    

     

 
       
    </script>
</head>
<body>
    <form id="form1" runat="server">
    <div>
         <ul id="tree"></ul>
    </div>
    </form>
</body>

以上方法仅仅实现功能，未经测试