如何通過管道角4來渲染UL列表？

Question

我有以下UL名單：

<li class="item" *ngFor="let lang of languages | orderBy: 'def'">{{lang.id}}</li> 

哪裏orderBy是管：

import { Pipe, PipeTransform } from '@angular/core'; 
import * as _ from 'lodash'; 
@Pipe({ 
    name: 'orderBy' 
}) 
export class OrderBy implements PipeTransform { 
    transform(array: any[], orderBy: any) { 
    return _.sortBy(array, orderBy) 

    } 
} 

的languages對象是：

[ { "id": 1, "code": "fr", "active": true, "def": 0, "hide": false }, { "id": 2, "code": "ru", "active": true, "def": 1, "hide": false } ] 

你可以通過屬性"def"看到這條管道種類。在我的情況下，第一個元素li應該是{ "id": 2, "code": "ru", "active": true, "def": 1, "hide": false }。

但是我發現它並沒有被發現。該模板未呈現。

我選中此：

var c = _.sortBy([ { "id": 1, "code": "fr", "active": true, "def": 0, "hide": false }, { "id": 2, "code": "ru", "active": true, "def": 1, "hide": false } ],"def"); 

它返回我反對：

{id: 1, code: "fr", active: true, def: 0, hide: false} 
{id: 2, code: "ru", active: true, def: 1, hide: false} 

正如你可以看到def: 1元素不是排在首位。

Answer 1

用戶array.reverse

_.sortBy([ { "id": 1, "code": "fr", "active": true, "def": 0, "hide": false }, { "id": 2, "code": "ru", "active": true, "def": 1, "hide": false } ],"def").reverse()