可观察到的另一个包含数组的数组-过滤器

Question

我有一个可以观察到的笔记

this.notes$ = this.NoteService.notes$

notes$ = 

0: {id: 4, user_id: 1, body: null, reminder: null, created_at: '2022-08-22T17:44:37.000000Z', …}
1: {id: 3, user_id: 1, body: 'die neuere', reminder: null, created_at: '2022-05-22T10:04:26.000000Z', …}
2: {id: 2, user_id: 1, body: 'Klappt das mit den Notizen?\n\n\nAuch mit Absätzen?', reminder: '2022-05-22 00:00:00', created_at: '2022-05-15T19:34:36.000000Z', …}
3:
body: "Meine Lieblingsnotiz"
created_at: "2022-05-15T18:13:43.000000Z"
id: 1
reminder: null
tags: Array(2)
0: {id: 1, name: 'Arbeit', slug: 'arbeit', created_at: null, updated_at: null, …}
1: {id: 4, name: 'Backlog', slug: 'backlog', created_at: null, updated_at: null, …}
length: 2
[[Prototype]]: Array(0)
title: "Test Notiz"
updated_at: "2022-05-15T18:13:57.000000Z"
user_id: 1

现在，我在html页面中有了开关，在那里我喜欢为标记激活一个过滤器。我把过滤器推到一个额外的数组，

['backlog', 'arbeit', 'email']

但是我没有办法通过阵列滤波器进行可观察到的滤波。我在想一件事

this.notes$ = this.NoteService.notes$.pipe(
      map(notes=> notes
        //.filter(t=> (!t.tags || t.tags.some(ai => this.filterTag.includes(ai))))   
        //.filter(t=> t.tags?.length > 0 && t.tags?.includes(this.filterTag) 
        //.filter(t=> t.tags!=undefined && t.tags.includes(this.filterTag))
        ))

也许你有个主意给我？提前感谢

Answer 1

我用另一种方式修复了它

this.notes$ = this.NoteService.notes$.pipe(
      map((notes => notes
        .filter(t=> this.filterTaginNote(t)
        
      ))))
  ;

filterTaginNote(note: Note){
    if (this.filterTag.length == 0){return true}
    if (note.tags){
      for(var i = 0; i < note.tags?.length; i++){
        if (this.filterTag.includes(note.tags[i].slug)){
          return true;
        }
      }
    }
    return false;

  }

Answer 2

检查是否为一个数组，然后执行常规逻辑，否则只需使用数组的includes方法在数组中找到该字符串。如果不存在标记，则返回原始数组本身！

this.notes$ = this.NoteService.notes$.pipe(
  map(notes=> notes.filter(t=> 
               t.tags && t.tags.length ? 
                   (
                   Array.isArray(this.filterTag) ? 
                     t.tags.some(x => this.filterTag.includes(x)) : 
                        t.tags.includes(this.filterTag) 
                          ): true
    ))