Question

我试图创建一个可以通过“闹钟”过滤掉我的对象的计算函数，

所以我创建了一个名为filteredAlarms的计算函数，在我的循环中我做了一个v-for循环：

<li class="event-log__item timeline__item" v-for="(item, key) in filteredAlarms" :key="key">

在我的过滤器中尝试执行以下操作：

let filteredAlarms = Object.keys(this.eventLog).forEach(key => {
  this.eventLog[key].filter(item => {
    return item.type.indexOf("alarm") > -1
  });
});

return filteredAlarms

不幸的是，这不起作用 - 我得到一个错误：TypeError：this.eventLog.filter不是函数

我做错了什么？ :)

我试图过滤的对象类似于下面的对象：

"system_events": {
    "1013": [{
        "id": 25899,
        "timestamp": "2017-08-15T21:26:42Z",
        "type": "alarm",
        "code": 190,
        "title": "",
        "description": "",
        "appeared": "2017-08-15T21:26:40Z",
        "disappeared": null,
        "acknowlegded": null,
        "solved": null,
        "system_name": "Randers pr 44b sidste station"
    }, 
    {
        "id": 26157,
        "timestamp": "2017-08-15T21:32:17Z",
        "type": "warning",
        "code": 190,
        "title": "",
        "description": "",
        "appeared": "2017-08-15T21:32:06Z",
        "disappeared": null,
        "acknowlegded": null,
        "solved": null,
        "system_name": "Randers pr 44b sidste station"
    }, 
    {
        "id": 26387,
        "timestamp": "2017-08-15T21:37:38Z",
        "type": "info",
        "code": 190,
        "title": "",
        "description": "",
        "appeared": "2017-08-15T21:37:33Z",
        "disappeared": null,
        "acknowlegded": null,
        "solved": null,
        "system_name": "Randers pr 44b sidste station"
    }],
    "1015": [{
        "id": 23777,
        "timestamp": "2017-08-15T20:38:08Z",
        "type": "alarm",
        "code": 191,
        "title": "",
        "description": "",
        "appeared": "2017-08-15T20:38:00Z",
        "disappeared": null,
        "acknowlegded": null,
        "solved": null,
        "system_name": "Favrskov Svenstrup gyvelvej"
    }, 
    {
        "id": 23779,
        "timestamp": "2017-08-15T20:38:08Z",
        "type": "alarm",
        "code": 190,
        "title": "",
        "description": "",
        "appeared": "2017-08-15T20:37:58Z",
        "disappeared": null,
        "acknowlegded": null,
        "solved": null,
        "system_name": "Favrskov Svenstrup gyvelvej"
    }, 
    {
        "id": 23841,
        "timestamp": "2017-08-15T20:39:41Z",
        "type": "alarm",
        "code": 192,
        "title": "",
        "description": "",
        "appeared": "2017-08-15T20:39:31Z",
        "disappeared": null,
        "acknowlegded": null,
        "solved": null,
        "system_name": "Favrskov Svenstrup gyvelvej"
    }, 
    {
        "id": 25243,
        "timestamp": "2017-08-15T21:12:03Z",
        "type": "alarm",
        "code": 191,
        "title": "",
        "description": "",
        "appeared": "2017-08-15T21:11:55Z",
        "disappeared": null,
        "acknowlegded": null,
        "solved": null,
        "system_name": "Favrskov Svenstrup gyvelvej"
    }, 
    {
        "id": 25529,
        "timestamp": "2017-08-15T21:18:11Z",
        "type": "alarm",
        "code": 190,
        "title": "",
        "description": "",
        "appeared": "2017-08-15T21:18:00Z",
        "disappeared": null,
        "acknowlegded": null,
        "solved": null,
        "system_name": "Favrskov Svenstrup gyvelvej"
    }]
}

Answer 1

使用forEach，你不会过滤任何东西，你会迭代。并且内部过滤器返回新数组，因此它也不会更改eventLog[key]。

尝试这样的事情：

let filteredAlarams = {}

Object.keys(this.eventLog).forEach(key => {
  filteredAlarams[key] = this.eventLog[key].filter(item => {
    return item.type.indexOf("alarm") > -1
  });
});

return filteredAlarms

Answer 2

首先，filteredAlarms的值为undefined，因为forEach不会返回任何内容。

其次，您应该知道filter()返回一个新数组。您没有在任何地方使用新的过滤数组。

看起来像这样

const filteredAlarms = Object.keys(this.eventLog).reduce((result, key) => {
     result[key] = this.eventLog[key].filter(item => {
       return item.type.indexOf("alarm") > -1
     })

     return result
}, {})

return filteredAlarms

然后是

TypeError: this.eventLog.filter is not a function

我猜测你是在尝试迭代上面发布的整个对象，但是你应该迭代data.system_events属性。

在Vue中过滤，嵌套数组

2 个答案: