js 遍历多叉树怎么遍历

    var s = '[{"thisNode":"10000480","prientNode":"10000480","level":"0","isLeaf":"0","children":[{"level":"1","prientNode":"10000440","thisNode":"10000480","isLeaf":"1","children":[]},{"level":"1","prientNode":"10000441","thisNode":"10000480","isLeaf":"0","children":[{"level":"2","prientNode":"100660","thisNode":"10000441","isLeaf":"1","children":[]}]}]}]';
        function getChildrenStr(node) {
            var r = '', children = node.children;
            if (children && children.length > 0) {
                var level = parseInt(children[0].level, 10), preBlank = '　　　　　　　　　'.substr(0, level);
                for (var i = 0; i < children.length; i++) {
                    r += '<br>' + preBlank + children[i].prientNode + getChildrenStr(children[i]);
                }
            }
            return r;
        }
        var o = eval('(' + s + ')');//转为json对象
        var r = '';
        for (var i = 0; i < o.length; i++) {
            r += '<br>' + o[i].prientNode + getChildrenStr(o[i]);
        }
        document.write(r);