Easy UI Tree 动态加载tree、异步加载

刚接触Easy UI，很多东西还是粗放式的，望理解。

后台采用的是ahsx 

代码如下：

 Handler.ashx

<%@ WebHandler Language="C#" Class="Handler" %>

using System;
using System.Web;

public class Handler : IHttpHandler {
    
    public void ProcessRequest (HttpContext context) {
        context.Response.ContentType = "text/plain";
        string method = context.Request["action"];
        switch (method)
        {
            case "GetModule":
                {
                    string a = context.Request.Params["id"];//参数为id
                    TreeViewCommon treeViewCommon = new TreeViewCommon();
                    
                    context.Response.Write(treeViewCommon.GetModule());
                    break;
                }
            default:
                break;
        }
    }
 
    public bool IsReusable {
        get {
            return false;
        }
    }
}

 Cs文件如下：TreeViewCommon.cs

 public  string GetModule() 

    {
        string sql = "SELECT m.ID, m.Name, m.ParentID, m.Url, m.Ico FROM Module m ORDER BY m.Level, m.[Index]";
        DataTable dt = GetTable(sql);
        return TableToEasyUITreeJson(dt, "ParentID", "0", "ID", "Name").Substring(12);
    }
    /// <summary>
    /// 递归将DataTable转化为适合jquery easy ui 控件tree ,combotree 的 json
    /// 该方法最后还要 将结果稍微处理下,将最前面的,"children" 字符去掉.
    /// </summary>
    /// <param name="dt">要转化的表</param>
    /// <param name="pField">表中的父节点字段</param>
    /// <param name="pValue">表中顶层节点的值,没有 可以输入为0</param>
    /// <param name="kField">关键字字段名称</param>
    /// <param name="TextField">要显示的文本 对应的字段</param>
    /// <returns></returns>
    public static string TableToEasyUITreeJson(DataTable dt, string pField, string pValue, string kField, string TextField)
    {
        StringBuilder sb = new StringBuilder();
        string filter = String.Format(" {0}='{1}' ", pField, pValue);//获取顶级目录.
        DataRow[] drs = dt.Select(filter);
        if (drs.Length < 1)
            return "";
        sb.Append(",\"children\":[");
        foreach (DataRow dr in drs)
        {
            string pcv = dr[kField].ToString();
            sb.Append("{");
            sb.AppendFormat("\"id\":\"{0}\",", dr[kField].ToString());
            sb.AppendFormat("\"text\":\"{0}\"", dr[TextField].ToString());
            sb.Append(TableToEasyUITreeJson(dt, pField, pcv, kField, TextField).TrimEnd(','));
            sb.Append("},");
        }
        if (sb.ToString().EndsWith(","))
        {
            sb.Remove(sb.Length - 1, 1);
        }
        sb.Append("]");
        return sb.ToString();

    }

 aspx文件如下：

导入jquery-1.7.2.min.js、jquery.easyui.min.js、和自己的js（我在这里叫tree.js）文件
加入：
<ul id="mytree" class="easyui-tree"></ul>  

 tree.js文件如下

  

var dd = '[{"id":"0001","text":"1","children":[{"id":"00010001","text":"4","children":[{"id":"000100010001","text":"7","children":[{"id":"0001000100010001","text":"9","children":[{"id":"00010001000100010001","text":"10","children":[{"id":"000100010001000100010001","text":"11","children":[{"id":"0001000100010001000100010001","text":"12"}]}]}]}]},{"id":"000100010002","text":"8"}]},{"id":"00010002","text":"5"},{"id":"00010003","text":"6"}]},{"id":"0002","text":"2"},{"id":"0003","text":"3"}]';
    $(function () {
        $('#mytree').tree({
            //                data: eval(dd)
            //                onClick: function (node) {
            //                    $('#mytree').tree('beginEdit', node.target);
            //                }

            url: 'Handler.ashx?action=GetModule'
        });
    });

 

第二种方式，运用扩展实现一步加载

 扩展内容如下：

(function () {
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
//地址：http://git.oschina.net/gson/jeasyuicn-ext/tree/master/ext.easyui/ext.tree/properties.loader
//用法：
//*带参数初始化

//$("#tree").tree({
//    url:'tree.do'
//    queryParams:{pid:1}
//});

//*参数变更

//$("#tree").tree("setQueryParams",{pid:1});


//重写tree的loader
$.extend($.fn.tree.defaults, {
    loader: function (param, success, error) {
        var opts = $(this).tree("options");
        if (!opts.url) {
            return false;
        }
        if (opts.queryParams) {
            param = $.extend({}, opts.queryParams, param);
        }
        $.ajax({
            type: opts.method,
            url: opts.url,
            data: JSON2.stringify(param),
            dataType: "text",
            contentType: "application/json; charset=utf-8", //application/json
            success: function (data) {
                success(JSON2.parse(data));
            },
            error: function () {
                error.apply(this, arguments);
            }
        });
    },
    queryParams: {}
});
//设置参数
$.extend($.fn.tree.methods, {
    setQueryParams: function (jq, params) {
        return jq.each(function () {
            $(this).tree("options").queryParams = params;
        });
    }
});
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
})(jQuery);

调用方法如下：

    //运用扩展实现Tree的异步加载
    //$("#menu").tree("setQueryParams", { "parentID": 0 });
    $("#menu").tree({
        url: 'http://ehlccs.cn/ControlServices.svc/GetAsynEasyTree',
        queryParams: { "parentID": 0 },
        loadFilter: function (data) { //loadFilter 用于webServices、服务等【因为前面多个d】
            if (data.d) {
                return eval('(' + data.d + ')');
            } else {
                return eval('(' + data + ')');
            }
        },
        onBeforeExpand: function (node) {
            $("#menu").tree("setQueryParams", { "parentID": node.id });
            $('#menu').tree('options').url = "http://ehlccs.cn/ControlServices.svc/GetAsynEasyTree";
        }
    });
    

数据层方法：

/// <summary>
        /// 获取菜单信息，异步加载Tree
        /// </summary>
        /// <param name="parentID">ParentID</param>
        /// <returns></returns>
        public DataTable GetAsynTree(long parentID)
        {
            var dataManager = new DataManager("TreeDB", "GetAsynTree");
            IOHelper.WriteLine(@"E:\a.txt", parentID.ToString());
            dataManager.SetParameters("@ParentID", Convert.ToInt64(parentID));
            DataTable dt = new DataTable();
            dataManager.ExecuteDataTable(dt);
            return dt;
        }

   #region DataTable转EasyUiTree的Json格式
        /// <summary>
        /// DataTable转EasyUiTree的Json格式 【内部方法，不做过多验证】
        /// </summary>
        /// <param name="dt">要转化的表</param>
        /// <param name="pField">父节点对应字段</param>
        /// <param name="pValue">父节点的值，默认为"0"</param>
        /// <param name="idField">ID对应的字段</param>
        /// <param name="nameField">Name对应的字段</param>
        /// <param name="isParentField">是否是父节点对应的字段</param>
        /// <param name="isChooseParentNode">是否选择父节点，有单选框、复选框的时候用；true：checkbox radio 可以选择父节点/子节点；false：radio 只能选择叶子节点</param>
        /// <param name="url">url对应字段，可以为null  ""</param>
        /// <param name="icon">图片对应字段，可以为null  ""</param>
        /// <returns></returns> 
        private static string CartDataTableToTreeJson1(DataTable dt, string pField, string pValue, string idField, string nameField, string isParentField, bool? isChooseParentNode, string url, string icon)
        {

            StringBuilder sb = new StringBuilder();
            string filter = String.Format(" {0}={1} ", pField, pValue); //获取顶级目录.


            DataRow[] drs = dt.Select(filter);
            if (drs.Length < 1)
                return "";
            sb.Append(",\"children\":[");
            foreach (DataRow dr in drs)
            {
                IOHelper.WriteLine(@"E:\a.txt", dr[idField].ToString());
                string pcv = dr[idField].ToString();
                sb.Append("{");
                string strIsParent = dr[isParentField].ToString().Trim().ToLower();

                //string strIsParent = "false";
                if (strIsParent.Equals("true"))
                {
                    if (!string.IsNullOrWhiteSpace(url))
                    {
                        sb.AppendFormat("\"id\":\"{0}\",", dr[idField].ToString().Trim() + "," + dr[url].ToString().Trim());
                    }
                    else
                    {
                        sb.AppendFormat("\"id\":\"{0}\",", dr[idField].ToString().Trim());
                    }
                }
                else
                {
                    sb.AppendFormat("\"id\":\"{0}\",", dr[idField].ToString().Trim());
                }
                sb.AppendFormat("\"text\":\"{0}\",", dr[nameField].ToString().Trim());

                if (!string.IsNullOrWhiteSpace(icon))
                    sb.AppendFormat("\"iconCls\":\"{0}\",", dr[icon].ToString().Trim());

                //if (strIsParent.Equals("false"))
                //    if (!string.IsNullOrWhiteSpace(url))
                //    {
                //        sb.Append("\"attributes\":{");
                //        sb.AppendFormat("\"url\":\"{0}\",", dr[url].ToString().Trim());
                //        sb.Append("},");
                //    }

                //if (isChooseParentNode.Equals(false))
                //    if (strIsParent.Equals("true"))
                //        sb.AppendFormat("\"nocheck\":\"{0}\",", true);
                sb.AppendFormat("\"state\":\"{0}\"", strIsParent.Equals("true") ? "open" : "closed");

                sb.Append(CartDataTableToTreeJson1(dt, pField, pcv, idField, nameField, isParentField, isChooseParentNode, url, icon).TrimEnd(','));
                sb.Append("},");
            }
            if (sb.ToString().EndsWith(","))
            {
                sb.Remove(sb.Length - 1, 1);
            }
            sb.Append("]");
            return sb.ToString();
        }
        #endregion




SQL语句：

<DataCommand Name="GetAsynTree" CommandType="Text"  CommandDescrip="获取菜单信息，异步加载Tree">
    <CommandText>
      <![CDATA[
       --DECLARE @ParentID BIGINT
        --SET @ParentID = 0

        DECLARE @IsLeafNode BIT
        SET @IsLeafNode = 0

        SELECT m.ID, m.Name, m.[Url], m.Icon, m.[Level], m.[Index], m.IsEnabled,m.ParentID, m.SecondAncestorID,isnull(n.ChildNodesNumber,0) ChildNodesNumber,isnull(n.IsLeafNode,1) IsLeafNode FROM Module m
        LEFT  JOIN 
        (
        SELECT ParentID ID,COUNT(ParentID) ChildNodesNumber, @IsLeafNode IsLeafNode FROM Module
        GROUP BY ParentID
        ) n
        ON m.ID=n.ID
        WHERE  ParentID=@ParentID
      ]]>
    </CommandText>
    <Parameters>
      <!--<Parameter Name="@DomainAccount" Size="10" DbType="AnsiString" Direction="Input"/>-->
      <Parameter Name="@ParentID" DbType="Int64"/>
    </Parameters>