异步记载树默认展开

异步记载树默认展开：
        1、页面进来加载方法：expandAll();
        2、异步加载回调函数：onAsyncSuccess: zTreeOnAsyncSuccess
        3、然后加入下面内容：
        var curStatus = "init", curAsyncCount = 0, asyncForAll = false,goAsync = false;
        function beforeAsync() {
            curAsyncCount++;
        }
        function zTreeOnAsyncSuccess(event, treeId, treeNode, msg) {
            curAsyncCount--;
            if (curStatus == "expand") {
                expandNodes(treeNode.children);
            } else if (curStatus == "async") {
                asyncNodes(treeNode.children);
            }

            if (curAsyncCount <= 0) {
                if (curStatus != "init" && curStatus != "") {
                    asyncForAll = true;
                }
                curStatus = "";
            }
        }
        function expandAll() {
            if (!check()) {
                return;
            }
            var zTree = $.fn.zTree.getZTreeObj("fitTypeTree");
            if (asyncForAll) {
                zTree.expandAll(true);
            } else {
                expandNodes(zTree.getNodes());
                if (!goAsync) {
                    curStatus = "";
                }
            }
        }
        function check() {
            if (curAsyncCount > 0) {
                return false;
            }
            return true;
        }
        function expandNodes(nodes) {
            if (!nodes) return;
            curStatus = "expand";
            var zTree = $.fn.zTree.getZTreeObj("fitTypeTree");
            for (var i=0, l=nodes.length; i<l; i++) {
                zTree.expandNode(nodes[i], true, false, false);
                if (nodes[i].isParent && nodes[i].zAsync) {
                    expandNodes(nodes[i].children);
                } else {
                    goAsync = true;
                }
            }
        }
        function asyncNodes(nodes) {
            if (!nodes) return;
            curStatus = "async";
            var zTree = $.fn.zTree.getZTreeObj("fitTypeTree");
            for (var i=0, l=nodes.length; i<l; i++) {
                if (nodes[i].isParent && nodes[i].zAsync) {
                    asyncNodes(nodes[i].children);
                } else {
                    goAsync = true;
                    zTree.reAsyncChildNodes(nodes[i], "refresh", true);
                }
            }
        }