我正在構(gòu)建一個(gè) Angular 7 應(yīng)用程序。在這個(gè)應(yīng)用程序中，我從服務(wù)器獲取 JSON 數(shù)據(jù)，然后我想按特定鍵對(duì)其進(jìn)行分組。我設(shè)法做到了這一點(diǎn)，但我不再有數(shù)組而是某種對(duì)象。啟動(dòng) JSON 數(shù)據(jù)[{    "id": 67,    "survey_id": 26,    "question_id": 63,    "user_id": 35,    "privacy": null,    "score": null,    "comment": "A nice little comment",    "binary": null,    "reasons": null,    "preferences": "{}",    "created_at_date": "2019-09-18",    "created_at_time": "19:53",    "user": {        "id": 35,        "fullname": "Michael Palin"    },    "can_manage": true},{    "id": 68,    "survey_id": 26,    "question_id": 64,    "user_id": 4,    "privacy": null,    "score": null,    "comment": "Another little comment",    "binary": null,    "reasons": null,    "preferences": "{}",    "created_at_date": "2019-09-18",    "created_at_time": "19:53",    "user": {        "id": 4,        "fullname": "Roland Smacker"    },    "can_manage": true},{    "id": 69,    "survey_id": 26,    "question_id": 65,    "user_id": 4,    "privacy": null,    "score": null,    "comment": "Some more comments",    "binary": null,    "reasons": null,    "preferences": "{}",    "created_at_date": "2019-09-18",    "created_at_time": "19:53",    "user": {        "id": 4,        "fullname": "Roland Smacker"    },    "can_manage": true},}]這是我的分組代碼setupStats() {    const groupBy = (array, key) => {      return array.reduce((result, currentValue) => {        (result[currentValue[key]] = result[currentValue[key]] || []).push(          currentValue        );        return result;      }, {});    };    const grouped = groupBy(this.collection, 'user_id');    console.log(grouped);  }這是輸出{4: Array(3), 35: Array(1)}4 和 35 是 user_ids。我希望他們獲取數(shù)組的一部分，以便我可以循環(huán)它們，而我現(xiàn)在不能這樣做。