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如何对对象数组和数组子集进行排序

[英]How to sort array of objects and subset of array

架构

var my_array = [ 
{
    "title": "a",
    "pinned": {
        "status": "true",
        "order": "1"
    }
},
{
    "title": "d",
    "pinned": {
        "status": "false",
        "order": "n/a"
    }
},
{
    "title": "c",
    "pinned": {
        "status": "true",
        "order": "0"
    }
},
{
    "title": "b",
    "pinned": {
        "status": "false",
        "order": "n/a"
    }
}
];

期望的行为

title按字母顺序对对象进行排序,
除非它们的pinned状态为true
在这种情况下,将此项目的“子集”移动到数组的开头,
按其pinned.order值排序。

一个示例场景是一个论坛,该论坛的帖子按日期排序,但最上面的粘性帖子按定义的顺序排序。

因此,原始架构将显示为:

[ 
{// i am at the top, because i have a pinned status of true and order of 0  
    "title": "c",
    "pinned": {
        "status": "true",
        "order": "0"
    }
},
{// i am second from the top, because i have a pinned status of true and order of 1  
    "title": "a",
    "pinned": {
        "status": "true",
        "order": "1"
    }
},
{// i follow in alphabetical order 
    "title": "b",
    "pinned": {
        "status": "false",
        "order": "n/a"
    }
},
{// i follow in alphabetical order 
    "title": "d",
    "pinned": {
        "status": "false",
        "order": "n/a"
    }
}
]

我尝试过的

my_array.sort(function(a, b) {
    return a.pinned.order.localeCompare(b.pinned.order) || a.title.localeCompare(b.title);
});

根据以下答案:

https://stackoverflow.com/a/45741804

我也尝试过...

我考虑过根据pinned.status的值创建两个单独的数组,分别对它们进行排序,然后重新组合(如下所示),但是我想知道是否还有更优雅的方法?

var my_array = [ 
{
    "title": "a",
    "pinned": {
        "status": "true",
        "order": "1"
    }
},
{
    "title": "d",
    "pinned": {
        "status": "false",
        "order": "n/a"
    }
},
{
    "title": "c",
    "pinned": {
        "status": "true",
        "order": "0"
    }
},
{
    "title": "b",
    "pinned": {
        "status": "false",
        "order": "n/a"
    }
}
];


var my_subset = [];

for (var i = 0; i < my_array.length; i++) {

    if (my_array[i].pinned.status === "true") {
        // add to subset
        my_subset.push(my_array[i]);
        // remove from original array
        my_array.splice(i, 1);
    }

}

// sort "pruned" original array alphabetically
my_array.sort(function(a, b) {
    return a.title.localeCompare(b.title);
});

// sort subset array by pinned.order
my_subset.sort(function(a, b) {
    return a.pinned.order.localeCompare(b.pinned.order, undefined, { numeric: true });
});

// prepend subset to original array
var new_array = my_subset.concat(my_array);

// array is sorted as desired
console.log(new_array);

首先通过将数字字符串设为数字,并将布尔字符串设为布尔值来修复数据:

for (const item of my_array) {
    item.pinned.status = JSON.parse(item.pinned.status);
    item.pinned.order = Number(item.pinned.order);
}

现在,您不必将它们作为字符串进行比较。 否则,您的方法基本上没问题,您只是忘记了最重要的指示符,即某个项目是否应该到达顶部:它的pinned.status 首先进行比较,以使任何固定项目都在任何未固定项目之前。

my_array.sort(function(a, b) {
    return -(a.pinned.status - b.pinned.status) // reverse: true before false
    || (a.pinned.status // equal to b.pinned.status
      ? a.pinned.order - b.pinned.order
      : a.title.localeCompare(b.title));
});

 var my_array = [{ "title": "a", "pinned": { "status": true, "order": 1 } }, { "title": "d", "pinned": { "status": false, "order": 0 } }, { "title": "c", "pinned": { "status": true, "order": 0 } }, { "title": "b", "pinned": { "status": false, "order": 0 } } ]; my_array.sort(function(a, b) { return -(a.pinned.status - b.pinned.status) // reverse: true before false || (a.pinned.status // equal to b.pinned.status ? a.pinned.order - b.pinned.order : a.title.localeCompare(b.title)); }); console.log(my_array); 

你也可以

my_array.sort(function(a, b) {
    return -(a.pinned.status - b.pinned.status) // reverse: true before false
    || a.pinned.order - b.pinned.order
    || a.title.localeCompare(b.title);
});

因为未固定的商品具有相同的顺序( NaN ),但前者更为明确。

尝试一下:

my_array.sort(function(a, b) {
    return a.title.localeCompare(b.title);
}).sort(function(a, b) {
    return a.pinned.order.localeCompare(b.pinned.order)
});

如果可以使用Lodash(Java实用程序库),则可以使用orderBy或sortBy:

在项目中使用Lodash:

<script src="lodash.js"></script>

使用orderBy进行排序:

_.orderBy(my_array, [function(e) { return e.pinned.status}, 'title'], ['asc', 'asc']);

关于orderBy的更多信息

你去那里:

 var my_array = [ { "title": "a", "pinned": { "status": "true", "order": "1" } }, { "title": "d", "pinned": { "status": "false", "order": "n/a" } }, { "title": "c", "pinned": { "status": "true", "order": "0" } }, { "title": "b", "pinned": { "status": "false", "order": "n/a" } } ]; var trueArr = []; var falseArr = []; var titleArr = []; var tempArr = [] for(var obj of my_array){ if(obj.pinned.status == "true"){ trueArr.push(obj); }else{ falseArr.push(obj); } } function sortArr(arr){ titleArr = []; tempArr = []; for(var obj of arr){ titleArr.push(obj.title); } titleArr = titleArr.sort(); for(var counter = 0; counter < arr.length; counter++){ tempArr.push(null); } for(var obj of arr){ tempArr[titleArr.indexOf(obj.title)] = obj; } for(counter = 0; counter < tempArr.length; counter++){ arr[counter] = tempArr[counter]; } } function addTrueFalseArr(arr){ for (var obj of arr){ my_array.push(obj) } } sortArr(trueArr); my_array = []; addTrueFalseArr(trueArr); sortArr(falseArr); addTrueFalseArr(falseArr); 

提取pinned = true所有对象,并将它们放入数组中。 然后,对于pinned = false对象也是如此。 然后,它会根据它们的标题(按字母顺序)对这两个数组进行排序,然后将原始数组设置为一个空数组-> [] ,然后将true项目附加到原始数组,最后附加false项目。

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