根据条件获取json(无限级)中指定的对象

JSON:

[
    {"id":"1","text":"电脑整机","parentid":"0","children":[
        {"id":"2","text":"笔记本","parentid":"1","children":[
            {"id":"31","text":"SONY","parentid":"2","children":[]},
            {"id":"23","text":"LENOVO","parentid":"2","children":[]},
            {"id":"25","text":"IBM","parentid":"2","children":[]},
            {"id":"26","text":"宏基","parentid":"2","children":[]},
            {"id":"27","text":"联想","parentid":"2","children":[]},
            {"id":"28","text":"联想2","parentid":"2","children":[]}
        ]},
        {"id":"3","text":"上网本","parentid":"1","children":[]},
        {"id":"4","text":"平板电脑","parentid":"1","children":[]},
        {"id":"5","text":"台式机","parentid":"1","children":[]},
        {"id":"6","text":"服务器","parentid":"1","children":[]}
    ]},
    {"id":"7","text":"电脑配件","parentid":"0","children":[
        {"id":"8","text":"CPU","parentid":"7","children":[]},
        {"id":"9","text":"主板","parentid":"7","children":[]},
        {"id":"10","text":"显卡","parentid":"7","children":[]},
        {"id":"11","text":"硬盘","parentid":"7","children":[]},
        {"id":"12","text":"内存","parentid":"7","children":[]},
        {"id":"13","text":"机箱","parentid":"7","children":[]},
        {"id":"14","text":"电源","parentid":"7","children":[]},
        {"id":"15","text":"显示器","parentid":"7","children":[]},
        {"id":"16","text":"刻录机/光驱","parentid":"7","children":[]},
        {"id":"17","text":"声卡","parentid":"7","children":[]},
        {"id":"18","text":"扩展卡","parentid":"7","children":[]}
    ]}
]

js:

var obj;

function searchtree(nodes,id) {
        $.each(nodes, function (i, n) {
        if (n.id == id) {
            obj = n;
            return false;
        }
        else {
            if (n.children.length > 0) {
                searchtree(n.children, id);
            }
        }
    });

    return obj;
}