如何访问RowDataPacket对象

Question

我目前正在使用Node-webkit开发桌面应用程序.在此过程中,我需要从本地MySQL数据库中获取一些数据.

查询工作正常,但我无法弄清楚如何访问结果.我将所有这些存储在一个数组中,然后传递给一个函数.在控制台中,它们看起来像这样:

RowDataPacket {user_id: 101, ActionsPerformed: 20}
RowDataPacket {user_id: 102, ActionsPerformed: 110}
RowDataPacket {user_id: 104, ActionsPerformed: 3}

这是查询结构:

var ret = [];
conn.query(SQLquery, function(err, rows, fields) {
    if (err)
        alert("...");
    else {
        for (var i of rows) 
            ret.push(i);
    }
    doStuffwithTheResult(ret);
}

如何在doStuffwithTheResult函数中检索它？价值观更重要,但如果我能得到钥匙也会很棒.

Answer 1

原来它们是普通物体,你可以通过它们访问它们user_id.

如果结果是数组,则必须使用new RowDataPacket(user_id, ...).

Answer 2

我最近也遇到了同样的问题,当我在express项目中使用waterline进行复杂查询时,使用SQL语句进行查询.

这是我的解决方案:首先将返回值(RowDataPacket对象)转换为字符串,然后将此字符串转换为json对象.

以下是代码:

//select all user (??????)
find: function(req, res, next){
    console.log("i am in user find list");
    var sql="select * from tb_user";

    req.models.tb_user.query(sql,function(err, results) {
        console.log('>> results: ', results );
        var string=JSON.stringify(results);
        console.log('>> string: ', string );
        var json =  JSON.parse(string);
        console.log('>> json: ', json);
        console.log('>> user.name: ', json[0].name);
        req.list = json;
        next();
    });
}

以下是控制台:

    >> results:  [ RowDataPacket {
    user_id: '2fc48bd0-a62c-11e5-9a32-a31e4e4cd6a5',
    name: 'wuwanyu',
    psw: '123',
    school: 'Northeastern university',                                                                                                                                           
    major: 'Communication engineering',                                                                                                                                            
    points: '10',
    datems: '1450514441486',
    createdAt: Sat Dec 19 2015 16:42:31 GMT+0800 (??????),                                                                                                  
    updatedAt: Sat Dec 19 2015 16:42:31 GMT+0800 (??????),                                                                                                  
    ID: 3,
    phone: 2147483647 } ]
>> string:  [{"user_id":"2fc48bd0-a62c-11e5-9a32-a31e4e4cd6a5","name":"wuwanyu","psw":"123","school":"Northeastern university","major":"Communication engineering","points":"10","datems":"1450514
441486","createdAt":"2015-12-19T08:42:31.000Z","updatedAt":"2015-12-19T08:42:31.000Z","ID":3,"phone":2147483647}]
>> json:  [ { user_id: '2fc48bd0-a62c-11e5-9a32-a31e4e4cd6a5',
    name: 'wuwanyu',
    psw: '123',
    school: 'Northeastern university',                                                                                                                                           
    major: 'Communication engineering',                                                                                                                                            
    points: '10',
    datems: '1450514441486',
    createdAt: '2015-12-19T08:42:31.000Z',
    updatedAt: '2015-12-19T08:42:31.000Z',
    ID: 3,
    phone: 2147483647 } ]
>> user.name:  wuwanyu

Answer 3

嗨，试试这个 100% 的作品：

results=JSON.parse(JSON.stringify(results))
doStuffwithTheResult(results); 

Answer 4

您可以通过Object.assign(target,... sources)将对象的所有可枚举属性复制到新属性:

trivial_object = Object.assign({}, non_trivial_object);

所以在你的场景中,它应该足以改变

ret.push(i);

至

ret.push(Object.assign({}, i));

Answer 5

您尝试使用不带 rowdatapacket 的 JSON 代码：

var ret = [];
conn.query(SQLquery, function(err, rows, fields) {
    if (err)
        alert("...");
    else {
        ret = JSON.stringify(rows);
    }
    doStuffwithTheResult(ret);
}

Answer 6

使用Object.prototype方法，JSON.parse(JSON.stringify(rows))返回对象，使用提取值Object.values()

var resultArray = Object.values(JSON.parse(JSON.stringify(rows)))

用法：

resultArray.forEach(function(v){ console.log(v) })