猫鼬字符串到 ObjectID

Question

我有一个带有 ObjectId 的字符串。

var comments = new Schema({
    user_id:  { type: Schema.Types.ObjectId, ref: 'users',required: [true,'No user id found']},
    post: { type: Schema.Types.ObjectId, ref: 'posts',required: [true,'No post id found']}....

export let commentsModel: mongoose.Model<any> = mongoose.model("comments", comments);

我是如何使用它的：

let comment = new commentsModel;
str = 'Here my ObjectId code' //
comment.user_id = str;
comment.post = str;
comment.save();

当我创建“评论”模型并分配字符串 user_id 值或发布时，我在保存时出错。我把console.log(comment) 的所有数据都分配给了vars。

我试试：

 var str = '578df3efb618f5141202a196';
    mongoose.mongo.BSONPure.ObjectID.fromHexString(str);//1
    mongoose.mongo.Schema.ObjectId(str);//2
    mongoose.Types.ObjectId(str);//3

1. TypeError: 对象函数 ObjectID(id) {
2. TypeError：无法调用未定义的方法“ObjectId”
3. TypeError：无法读取未定义的属性“ObjectId”

当然我也包括了猫鼬在所有呼叫之前

import * as mongoose from 'mongoose';

没有任何作用。

Answer 1

使用这个

 var mongoose = require('mongoose');
 var str = '578df3efb618f5141202a196';
 var mongoObjectId = mongoose.Types.ObjectId(str);

Answer 2

您想使用默认导出：

import mongoose from 'mongoose';

之后，mongoose.Types.ObjectId 将起作用：

import mongoose from 'mongoose';
console.log( mongoose.Types.ObjectId('578df3efb618f5141202a196') );

编辑： 完整示例（使用mongoose@4.5.5 测试）：

import mongoose from 'mongoose';

mongoose.connect('mongodb://localhost/test');

const Schema = mongoose.Schema;

var comments = new Schema({
    user_id:  { type: Schema.Types.ObjectId, ref: 'users',required: [true,'No user id found']},
    post: { type: Schema.Types.ObjectId, ref: 'posts',required: [true,'No post id found']}
});

const commentsModel = mongoose.model("comments", comments);

let comment = new commentsModel;
let str = '578df3efb618f5141202a196';
comment.user_id = str;
comment.post = str;
comment.save().then(() => console.log('saved'))
              .catch(e => console.log('Error', e));

数据库显示：

mb:test$ db.comments.find().pretty()
{
    "_id" : ObjectId("578e5cbd5b080fbfb7bed3d0"),
    "post" : ObjectId("578df3efb618f5141202a196"),
    "user_id" : ObjectId("578df3efb618f5141202a196"),
    "__v" : 0
}