我有一个JavaScript对象数组:

var objs = [ 
    { first_nom: 'Lazslo', last_nom: 'Jamf'     },
    { first_nom: 'Pig',    last_nom: 'Bodine'   },
    { first_nom: 'Pirate', last_nom: 'Prentice' }
];

如何在JavaScript中按last_nom的值对它们进行排序?

我知道排序(a,b),但这似乎只适用于字符串和数字。是否需要向对象添加toString()方法?


当前回答

对于工作狂:

const objectSorter = (p) => (a, b) => ((a, b) => a>b ? 1 : a<b ? -1 : 0)(a[p], b[p]);
objs.sort(objectSorter('first_nom'));

其他回答

使用Lodash或Undercore.js,这是小菜一碟:

const sortedList = _.orderBy(objs, [last_nom], [asc]); // Ascending or descending

这将按照按字母数字顺序传递给它的属性对两级嵌套数组进行排序。

function sortArrayObjectsByPropAlphaNum(property) {
    return function (a,b) {
        var reA = /[^a-zA-Z]/g;
        var reN = /[^0-9]/g;
        var aA = a[property].replace(reA, '');
        var bA = b[property].replace(reA, '');

        if(aA === bA) {
            var aN = parseInt(a[property].replace(reN, ''), 10);
            var bN = parseInt(b[property].replace(reN, ''), 10);
            return aN === bN ? 0 : aN > bN ? 1 : -1;
        } else {
            return a[property] > b[property] ? 1 : -1;
        }
    };
}

用法:

objs.sort(utils.sortArrayObjectsByPropAlphaNum('last_nom'));

如果您有嵌套对象

const objs = [{
        first_nom: 'Lazslo',
        last_nom: 'Jamf',
        moreDetails: {
            age: 20
        }
    }, {
        first_nom: 'Pig',
        last_nom: 'Bodine',
        moreDetails: {
            age: 21
        }
    }, {
        first_nom: 'Pirate',
        last_nom: 'Prentice',
        moreDetails: {
            age: 22
        }
    }];

nestedSort = (prop1, prop2 = null, direction = 'asc') => (e1, e2) => {
        const a = prop2 ? e1[prop1][prop2] : e1[prop1],
            b = prop2 ? e2[prop1][prop2] : e2[prop1],
            sortOrder = direction === "asc" ? 1 : -1
        return (a < b) ? -sortOrder : (a > b) ? sortOrder : 0;
    }

并称之为

objs.sort(nestedSort("last_nom"));
objs.sort(nestedSort("last_nom", null, "desc"));
objs.sort(nestedSort("moreDetails", "age"));
objs.sort(nestedSort("moreDetails", "age", "desc"));

简单答案:

objs.sort((a,b)=>a.last_nom.localeCompare(b.last_nom))

细节:

今天非常简单,您可以将字符串与localeCompare进行比较。正如Mozilla Doc所说:

localeCompare()方法返回一个数字,指示引用字符串在排序顺序上位于给定字符串之前、之后或与给定字符串相同。

    //example1:
    console.log("aaa".localeCompare("aab")); //-1
    console.log("aaa".localeCompare("aaa")); //0
    console.log("aab".localeCompare("aaa")); //1

    //example2:
    const a = 'réservé'; // with accents, lowercase
    const b = 'RESERVE'; // no accents, uppercase

    console.log(a.localeCompare(b));
    // expected output: 1
    console.log(a.localeCompare(b, 'en', { sensitivity: 'base' }));
    // expected output: 0

有关详细信息,请参阅Mozilla doclocaleCompare:

我没有看到任何类似于我的实现。此版本基于施瓦茨变换习惯用法。

function sortByAttribute(array, ...attrs) {
  // Generate an array of predicate-objects containing
  // property getter, and descending indicator
  let predicates = attrs.map(pred => {
    let descending = pred.charAt(0) === '-' ? -1 : 1;
    pred = pred.replace(/^-/, '');
    return {
      getter: o => o[pred],
      descend: descending
    };
  });
  // Schwartzian transform idiom implementation. AKA "decorate-sort-undecorate"
  return array.map(item => {
    return {
      src: item,
      compareValues: predicates.map(predicate => predicate.getter(item))
    };
  })
  .sort((o1, o2) => {
    let i = -1, result = 0;
    while (++i < predicates.length) {
      if (o1.compareValues[i] < o2.compareValues[i])
        result = -1;
      if (o1.compareValues[i] > o2.compareValues[i])
        result = 1;
      if (result *= predicates[i].descend)
        break;
    }
    return result;
  })
  .map(item => item.src);
}

下面是如何使用它的示例:

let games = [
  { name: 'Mashraki',          rating: 4.21 },
  { name: 'Hill Climb Racing', rating: 3.88 },
  { name: 'Angry Birds Space', rating: 3.88 },
  { name: 'Badland',           rating: 4.33 }
];

// Sort by one attribute
console.log(sortByAttribute(games, 'name'));
// Sort by mupltiple attributes
console.log(sortByAttribute(games, '-rating', 'name'));