从这个最初的问题,我将如何在多个字段应用排序?

使用这种稍作调整的结构,我将如何排序城市(上升)和价格(下降)?

var homes = [
    {"h_id":"3",
     "city":"Dallas",
     "state":"TX",
     "zip":"75201",
     "price":"162500"},
    {"h_id":"4",
     "city":"Bevery Hills",
     "state":"CA",
     "zip":"90210",
     "price":"319250"},
    {"h_id":"6",
     "city":"Dallas",
     "state":"TX",
     "zip":"75000",
     "price":"556699"},
    {"h_id":"5",
     "city":"New York",
     "state":"NY",
     "zip":"00010",
     "price":"962500"}
    ];

我喜欢的事实是,给出的答案提供了一个一般的方法。在我计划使用这段代码的地方,我将不得不对日期以及其他东西进行排序。“启动”对象的能力似乎很方便,如果不是有点麻烦的话。

我试图把这个答案构建成一个很好的通用示例,但我运气不太好。


当前回答

这是一个递归算法,按多个字段排序,同时有机会在比较之前格式化值。

var data = [
{
    "id": 1,
    "ship": null,
    "product": "Orange",
    "quantity": 7,
    "price": 92.08,
    "discount": 0
},
{
    "id": 2,
    "ship": "2017-06-14T23:00:00.000Z".toDate(),
    "product": "Apple",
    "quantity": 22,
    "price": 184.16,
    "discount": 0
},
...
]
var sorts = ["product", "quantity", "ship"]

// comp_val formats values and protects against comparing nulls/undefines
// type() just returns the variable constructor
// String.lower just converts the string to lowercase.
// String.toDate custom fn to convert strings to Date
function comp_val(value){
    if (value==null || value==undefined) return null
    var cls = type(value)
    switch (cls){
        case String:
            return value.lower()
    }
    return value
}

function compare(a, b, i){
    i = i || 0
    var prop = sorts[i]
    var va = comp_val(a[prop])
    var vb = comp_val(b[prop])

    // handle what to do when both or any values are null
    if (va == null || vb == null) return true

    if ((i < sorts.length-1) && (va == vb)) {
        return compare(a, b, i+1)
    } 
    return va > vb
}

var d = data.sort(compare);
console.log(d);

如果a和b相等,它将尝试下一个字段,直到没有可用字段。

其他回答

今天我做了一个相当通用的多特征排序器。你可以在这里看看byjs: https://github.com/Teun/thenBy.js

它允许您使用标准数组。排序,但使用firstBy(). thenby (). thenby()样式。它比上面发布的解决方案少了很多代码和复杂性。

为了简化操作,可以使用这些辅助函数。

您可以根据需要对任意多个字段进行排序。对于每个排序字段,指定属性名,然后可选地指定-1作为排序方向,以降序排序而不是升序排序。

const data = [ {"h_id":"3","city":"Dallas","state":"TX","zip":"75201","price":"162500"}, {"h_id":"4","city":"Bevery Hills","state":"CA","zip":"90210","price":"319250"}, {"h_id":"6","city":"Dallas","state":"TX","zip":"75000","price":"556699"}, {"h_id":"5","city":"New York","state":"NY","zip":"00010","price":"962500"}, {"h_id":"7","city":"New York","state":"NY","zip":"00010","price":"800500"} ] const sortLexically = (p,d=1)=>(a,b)=>d * a[p].localeCompare(b[p]) const sortNumerically = (p,d=1)=>(a,b)=>d * (a[p]-b[p]) const sortBy = sorts=>(a,b)=>sorts.reduce((r,s)=>r||s(a,b),0) // sort first by city, then by price descending data.sort(sortBy([sortLexically('city'), sortNumerically('price', -1)])) console.log(data)

homes.sort(function(a,b) { return a.city - b.city } );
homes.sort(function(a,b){
    if (a.city==b.city){
        return parseFloat(b.price) - parseFloat(a.price);
    } else {
        return 0;
    }
});

以下是我的简历,请参考,并举例说明:

function msort(arr, ...compFns) {
  let fn = compFns[0];
  arr = [].concat(arr);
  let arr1 = [];
  while (arr.length > 0) {
    let arr2 = arr.splice(0, 1);
    for (let i = arr.length; i > 0;) {
      if (fn(arr2[0], arr[--i]) === 0) {
        arr2 = arr2.concat(arr.splice(i, 1));
      }
    }
    arr1.push(arr2);
  }

  arr1.sort(function (a, b) {
    return fn(a[0], b[0]);
  });

  compFns = compFns.slice(1);
  let res = [];
  arr1.map(a1 => {
    if (compFns.length > 0) a1 = msort(a1, ...compFns);
    a1.map(a2 => res.push(a2));
  });
  return res;
}

let tstArr = [{ id: 1, sex: 'o' }, { id: 2, sex: 'm' }, { id: 3, sex: 'm' }, { id: 4, sex: 'f' }, { id: 5, sex: 'm' }, { id: 6, sex: 'o' }, { id: 7, sex: 'f' }];

function tstFn1(a, b) {
  if (a.sex > b.sex) return 1;
  else if (a.sex < b.sex) return -1;
  return 0;
}

function tstFn2(a, b) {
  if (a.id > b.id) return -1;
  else if (a.id < b.id) return 1;
  return 0;
}

console.log(JSON.stringify(msort(tstArr, tstFn1, tstFn2)));
//output:
//[{"id":7,"sex":"f"},{"id":4,"sex":"f"},{"id":5,"sex":"m"},{"id":3,"sex":"m"},{"id":2,"sex":"m"},{"id":6,"sex":"o"},{"id":1,"sex":"o"}]
// custom sorting by city
const sortArray = ['Dallas', 'New York', 'Beverly Hills'];

const sortData = (sortBy) =>
  data
    .sort((a, b) => {
      const aIndex = sortBy.indexOf(a.city);
      const bIndex = sortBy.indexOf(b.city);

      if (aIndex < bIndex) {
        return -1;
      }

      if (aIndex === bIndex) {
        // price descending
        return b.price- a.price;
      }

      return 1;
    });

sortData(sortArray);