jQuery.ZTree 刷新
错误的思路：
                                        $.ajax({
                                            //type:"GET",
                                            url: "DistrictClass.ashx?ReqType=dc&time="+Math.random(),
                                            dataType: "text",
                                            async: false,
                                            //data:'',
                                            success: function (msg) {
                                                       $(document).ready(function(){
            $.fn.zTree.init($("#treeDemo"), setting, zNodes);
        });
                                            }
                                        });

       var zNodes=<%=DiGuiTreeView()%>; //<%=TreeViewLeft()%>;
      
       <!--
        var setting = {
            data: {
                key: {
                    title:"cDCCode"
                },
                simpleData: {
                    enable: true
                }
            },
            async: {
                    enable:true,
                    url:"DistrictClass.ashx?ReqType=dc&time="+Math.random(),
                    asyncParam: ["id","pId","name","cDCCode","open"]
            },
            callback: {
                beforeClick: beforeClick,
                onClick: onClick
            }
        };

        var log, className = "dark";
        function beforeClick(treeId, treeNode, clickFlag) {
            className = (className === "dark" ? "":"dark");
            return (treeNode.click != false);
        }
        function onClick(event, treeId, treeNode, clickFlag) {
                        var ReqType = "LefDistrictClass";
                        var LefcDCCode = treeNode.cDCCode;
                        var aRequest2 = new XMLHttpRequest();
                        aRequest2.open("POST", "DistrictClass.ashx?ReqType=" + ReqType + "&LefcDCCode=" + LefcDCCode, true);
                        aRequest2.onreadystatechange = function () {
                            if (aRequest2.readyState == 4) {
                                if (aRequest2.responseText > 0) {
                                }
                                else {
                                    FreshDistrictClassRight();
                                }
                            }
                        }
                        aRequest2.send(null);
                        delcode = 0;
        }       
        function getTime() {
            var now= new Date(),
            h=now.getHours(),
            m=now.getMinutes(),
            s=now.getSeconds(),
            ms=now.getMilliseconds();
            return (h+":"+m+":"+s+ " " +ms);
        }

        $(document).ready(function(){
            $.fn.zTree.init($("#treeDemo"), setting, zNodes);
        });
        //-->
刷新节点：
                                    var zTree = $.fn.zTree.getZTreeObj("treeDemo");
                                    zTree.reAsyncChildNodes(null, "refresh");