exports.adduser = function(db) {
    return function(req, res) {
        // Get our form values. These rely on the "name" attributes
        var userName = req.body.username;
        var userEmail = req.body.useremail;
        var collection = db.get('users');
        var llll = collection.insert({
            "userid": userName,
            "password": userEmail,
        })
        if (llll) {
            res.location('http://baidu.com');
        } else {
            res.send("error")
        }
    }
};

数据库是插入成功的，但是不会正确跳转至到百度
报错是　500 TypeError: res.location is not a function

这是什么原因？