貓鼬數組不會排序

Question

mongodb文檔包含一個數組。 當使用貓鼬和graphql檢索到前端時，在數組上使用.sort（）會引發錯誤。

無法分配為只讀對象“ [對象數組]”的屬性“ 1”

但是，在完全相同的數組上使用.sort（）（這次是硬編碼）是可行的。

這里發生了什么事？！

const c = [ { slug: 'first-element',
    position: 1,
    alphaPos: 'B',
    type: 'heading',
    data: 'first-el B' },
{ slug: 'second-element',
    position: 2,
    alphaPos: 'C',
    type: 'textarea',
    data: 'second-el C' },
{ slug: 'third-element',
    position: 3,
    alphaPos: 'A',
    type: 'textarea',
    data: 'third-el A' },
{ slug: 'third-b-element',
    position: 3,
    alphaPos: 'D',
    type: 'textarea',
    data: 'third-el-22222 D' } ]

    // 'content' is the same as 'c' but it comes from mongoose, 
    // it throws an error
    console.log('content ==', content.sort())

    // 'c' is hard coded, no error is thrown
    console.log('content ==', c.sort())

    // console.log(c) and console.log(content) output exactly the same  array

[編輯：這是mongo文件]

    {
        "_id" : ObjectId("5a801422f1c5437466c5d285"),
        "createdAt" : ISODate("2018-02-11T10:00:02.800Z"),
        "id" : 1,
        "slug" : "interesting-story",
        "creatorId" : 3,
        "title" : "An interesting story",
        "image" : "/images/image1.jpg",
        "description" : "description",
        "content" : [ 
            {
                "slug" : "first-element",
                "position" : 1,
                "alphaPos" : "B",
                "type" : "heading",
                "data" : "first-el B"
            }, 
            {
                "slug" : "second-element",
                "position" : 2,
                "alphaPos" : "C",
                "type" : "textarea",
                "data" : "second-el C"
            }, 
            {
                "slug" : "third-element",
                "position" : 3,
                "alphaPos" : "A",
                "type" : "textarea",
                "data" : "third-el A"
            }, 
            {
                "slug" : "third-b-element",
                "position" : 3,
                "alphaPos" : "D",
                "type" : "textarea",
                "data" : "third-el-22222 D"
            }
        ],
        "__v" : 0
    }

這是架構

const postSchema = new Schema({
    id: { type: Number, required: true, unique: true },
    slug: { type: String, required: true, unique: true },
    creatorId: { type: Number, required: true },
    title: { type: String, required: true },
    image: { type: String, required: false },
    description: { type: String, required: true },
    content: { type: Array, required: false },
    createdAt: { type: Date, default: Date.now },
})

Answer 1

因為這些是2種不同的排序，所以取決於您所說的排序。 如果在數組（“硬編碼”）上調用它，它將使用默認的排序功能https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/sort，並且如果不能在mongodocument對象類型，無需編寫排序功能。

要使用貓鼬排序，必須在構建查詢時應用它

collection.find().sort().then(...)

Answer 2

萬一有人遇到相同的錯誤，我仍然無法解釋，但數組被視為對象，其中索引是鍵...

如果有人對此行為有一個解釋，我會很感興趣（與graphql？有關的是貓鼬嗎？也許與graphql-type-json包有關？）。

因此，要進行排序，這就是我正在做的事情（輸出一個數組）。

Object.keys(content).sort(a=>1).reduce((_sortedObj, key) => {
    _sortedObj.push(content[key])
    return _sortedObj
    }, [])