Jquery EasyUI tree 的异步加载（遍历指定文件夹，根据文件夹内的文件生成tree）

    private void SMT(HttpContext context)
    {
        string SqlConnection82 = System.Configuration.ConfigurationManager.AppSettings["LocalConnectionString"];
        string path = context.Server.MapPath(@"~/CISWeb/SMT_SOP");
        string id = string.Empty;
        List<string> filesNameList = getFiles(path);
        if (filesNameList.Count > 0)
            context.Response.Write(ListToJson(filesNameList,id));
        else
        {
            context.Response.Write("0");
        }       
    }
    /// <summary>
    /// 范围指定目录下的 文件夹/文件 数量
    /// </summary>
    /// <param name="path"></param>
    /// <returns></returns>
    private static List<string> getFiles(string path)
    {
        DirectoryInfo SMT_SOP = new DirectoryInfo(path);
        List<string> allFileList = new List<string>();
        DirectoryInfo[] allDir = SMT_SOP.GetDirectories();//获取文件夹数量
        foreach (DirectoryInfo d in allDir)
        {
            allFileList.Add("0|" + d.Name);
        }
        FileInfo[] allFile = SMT_SOP.GetFiles();//获取文件数量
        foreach (FileInfo fi in allFile)
        {
            allFileList.Add("1|" + fi.Name);
        }
        return allFileList;
    }
    /// <summary>
    /// 遍历指定文件夹，根据文件夹内的文件返回JSON
    /// </summary>
    /// <param name="filesNameList"></param>
    /// <param name="id">第一次调用这个方法的时候，id=""</param>
    /// <returns></returns>
    public string ListToJson(List<string> filesNameList,string id)
    {   
        StringBuilder sb2 = new StringBuilder();
        sb2.Append("[");
        for (int i = 0; i < filesNameList.Count; i++)
        {        
            if (filesNameList[i].ToString().Split('|')[0] == "0")
            { 
                sb2.Append("{ "id":" +id+ (i + 1).ToString() + ","text":"" + filesNameList[i].ToString().Split('|')[1] + "","state":"closed","children": [");              
                sb2.Append("]},");              
            }
            else
            {               
                sb2.Append("{"id":"+id + (i + 1).ToString() + ","text":"" + String.Format(filesNameList[i].ToString().Split('|')[1]) + ""},");              
            }

        }
        sb2.Remove(sb2.Length - 1, 1);
        sb2.Append("]");        
        return sb2.ToString();
    }

前台

$.ajax({
            type: "post",
            url: "../../ajax/Handler.ashx?action=SMT",
            data: {},
            success: function (result) {
                $("#menuDiv").dialog("open");//jQuery UI中的模态窗口
                var treeData = eval(result);
                $("#tt").tree({
                    data: treeData})
                }
            })

前台代码是部分代码，可能会有符号缺失