GeoJSON 数据保存但查询时 returns 未定义

Question

我有以下架构

    var RaceSchema = new Schema({
    account: {
        _id: String,
    name: String,
    country: String
    },
    raceName:  String,
    raceStartTime: Date,
    timezone: Number,
    trackTimeStart: Date,
    trackTimeFinish: Date,
    sponserImageURL: Array,     
    map: {
        center: Array,
        course: Object,
        zoomLevel: Number
    },
    boats: [{
            _id: String,
            handicaps: [{                   
                                name: String,
                    division: Number,
                    rating: Number,
                    correctedTime: Number,
                    place: Number
                            }]
    }],
    dtg: Number,
    eta: Date,
    finishTime: Date,
    socialMedia: [{
                    name: String,
                    link: String
    }],
    createdAt: { type: Date, default: new Date },
    updatedAt: Date
}, {
    collection: 'race'
});

我用它来存储 GeoJson 数据以及架构中显示的其他一些信息。我正在以下列格式保存数据（它是我在保存时从服务器获得的响应）

{
    "_id": "562bc48bfde8999f2995e61d",
    "raceStartTime": "2015-10-29T17:48:00.000Z",
    "trackTimeStart": "2015-10-24T17:48:00.000Z",
    "trackTimeFinish": "2015-10-24T17:48:00.000Z",
    "raceName": "Test ",
    "timezone": -4.5,
    "__v": 1,
    "updatedAt": "2015-10-24T17:49:16.912Z",
    "createdAt": "2015-10-24T17:39:45.587Z",
    "socialMedia": [],
    "boats": [{
        "_id": "55f6c2d39a2496d01d000002",
        "handicaps": []
    }],
    "map": {
        "center": [78.4651562, 17.4079808],
        "course": "{\"type\":\"LineString\",\"coordinates\":[[8639830.18113004,2037505.4259696582],[8738281.073561348,1972075.3297575472],[8619650.805662755,1928659.0976915671],[8645333.647166574,1981859.2693780498],[8598248.437742906,2021606.5240863415]]}",
        "zoomLevel": 8
    },
    "sponserImageURL": [],
    "account": {
        "_id": "55a7c944d65763c23d11dd96",
        "name": "Huy Tran"
    },
    "id": "562bc48bfde8999f2995e61d"
}

我正在将 map.course 的数据保存为从我的架构中看到的对象，其格式与我从开放层 api 收到的格式相同。我猜这是导致我的 findByIdAndRemove(id, callback); 到 return a

TypeError: Cannot read property '562bc2b5fde8999f2995e61c' of undefined

我该如何解决这个问题，以便我可以执行除在此架构上保存以外的其他操作

Answer 1

您似乎将 map.course 保存为 String（JSON 数据），而不是 Object。

如果那是 ol.format.GeoJSON 创建的 GeoJSON，请考虑使用 writeFeatureObject instead of writeFeature。它们 return 相同的结果，但第一个是实际的 JS 对象，第二个是带有 JSON.

的字符串

GeoJSON 数据保存但查询时 returns 未定义

GeoJSON data saving but returns undefined when queried

schema

mongoose

mongodb

geojson

openlayers-3