Need to push data in nested subdocument array

问题

I need to push data in nested subdocument array(replyComment):

This is an example of a document from my database:

{
  comments: [
    {
      replyComment: [],
      _id: 601a673735644c83e0aa1be3,
      username: 'xyz123@gmail.com',
      email: 'xyz213@gmail.com',
      comment: 'test123'
    },
    {
      replyComment: [],
      _id: 601a6c94d1653c618c75ceae,
      username: 'xyz123@gmail.com',
      email: 'xyz123@gmail.com',
      comment: 'reply test'
    }
  ],
  _id: 601a3b8038b13e70405cf9ea,
  title: 'latest test',
  snippet: 'latest test snippet',
  body: 'latest test body',
  createdAt: 2021-02-03T05:58:24.123Z,
  updatedAt: 2021-02-03T12:28:33.237Z,
  __v: 7
}

I am also mentioning my code snippet:

app.post('/:id/replyComment',(req,res) => { 
  const replyComm = new Comment(req.body);
  Topic.findById(req.params.id)
  .then((result) => {
    topic = result,
    console.log(topic);
    topic.update({_id:req.params.id, "comments._id": req.body.comment_id},
      { $push: {"comments.$.replyComment": {replyComment: replyComm}}}
    )
    topic.save()
    .then((result) => {
      // console.log(result);
        res.send({
          text: "Replied",
        })
    })
    .catch((err) => {
        console.log(err);
    });
  })
});

By running the request I am not getting any error but still the same documented is getting printed on my terminal and there is no change in "replyComment" subarray. Pls suggest how to make this work or any alternate method.

回答1:

I prefer to use objects instead of arrays by converting objects to the array Object.keys(data.comments)

{
  comments: 
    {
     '601a673735644c83e0aa1be3':{
        username: 'samyakjain971@gmail.com',
        email: 'samyakjain971@gmail.com',
        comment: 'test123'
      }
    },
    {
     '601a6c94d1653c618c75ceae':{
        username: 'samyakjain971@gmail.com',
        email: 'samyakjain971@gmail.com',
        comment: 'reply test'
     }
    },
  _id: 601a3b8038b13e70405cf9ea,
  title: 'latest test',
  snippet: 'latest test snippet',
  body: 'latest test body',
  createdAt: 2021-02-03T05:58:24.123Z,
  updatedAt: 2021-02-03T12:28:33.237Z,
  __v: 7
}

回答2:

define topic variable like this :

let topic = result;
console.log(topic);
topic.update({_id:req.params.id, "comments._id": req.body.comment_id},
    { $push: {"comments.$.replyComment": {replyComment: replyComm}}}
)

来源：https://stackoverflow.com/questions/66027692/need-to-push-data-in-nested-subdocument-array