Lodash : how to do a case insensitive sorting on a collection using orderBy?

I checked this answer but to achieve the same result, that is to get case-insensitive sorting, I need to use orderBy instead of sortBy since it gives the ability to specify the sort order.

The only way I found to achieve it was to create a cloned "middle" array mapped to lower case the name :

const users = [
{ name: 'A', age: 48 },
{ name: 'B', age: 34 },
{ name: 'b', age: 40 },
{ name: 'a', age: 36 }
];


let lowerCaseUsers = _.clone(users);


lowerCaseUsers = lowerCaseUsers.map((user) => {
user.name = user.name.toLowerCase();
return user;
});


const sortedUsers = _.orderBy(lowerCaseUsers, ['name'], ['desc']);


console.log(sortedUsers);

This seems really expensive and it will even be more complex with multiple sortings and dynamic properties names.

Is there a better idea ?

Here is a Plunker : https://plnkr.co/edit/i1ywyxjFctuNfHtPTcgG

76192 次浏览
小开
最佳答案

文件指定可以将函数作为“迭代器”传递:

[ iteratees = [ _. Identity ]](Array [] | Function [] | Object [] | string []) : 按照。

所以你可以

const users = [
{ name: 'A', age: 48 },
{ name: 'B', age: 34 },
{ name: 'b', age: 40 },
{ name: 'a', age: 36 }
];


const sortedUsers = _.orderBy(users, [user => user.name.toLowerCase()], ['desc']);
console.log(sortedUsers);
<script src="https://cdn.jsdelivr.net/lodash/4.13.1/lodash.min.js"></script>

小开

您可以将 Felix Kling 示例与 _. get 函数结合起来，按动态嵌套属性进行排序:

const _ = require('lodash');


let test = [{ a: {b:'AA'}},{a: {b:'BB'} }, {a: {b: 'bb'}}, {a:{b:'aa'}}];


let attrPath = 'a.b';


_.orderBy(test, [item => _.get(item, attrPath).toLowerCase()]);
小开

按多个属性排序:

const users = [
{ name: 'A', age: 48 },
{ name: 'B', age: 34 },
{ name: 'b', age: 40 },
{ name: 'a', age: 36 }
]


const nameSorter = user => user.name.toLowerCase()
const ageSorter = 'age'


const sortedUsers = _.orderBy(users, [nameSorter, ageSorter], ['desc', 'asc'])

提交答案