Angular 2使用嵌套的ngFor

Question

使用以下代碼時出現此錯誤：

找不到'對象'類型的不同支持對象'[object Object]'。

在進行嵌套的ngFor時，有沒有辦法解決這個問題？

import { Component,OnInit } from '@angular/core';

@Component({
  selector: 'my-app',
  template: `
    <div id="results">
      <div *ngFor="let mem of members">
        {{mem.id}}
        <div class="card-container">
          <div *ngFor="let case of mem.cases">
            {{case.id}}
          </div>
        </div>
      </div>
    </div>
    `,
})

export class AppComponent implements OnInit {
  public members = { "members": [ 
    { "name" : "Ana", "id" : "001", 
      "cases" : [
        {"id" : "992", "casenumber" : "882"},
        {"id" : "242", "casenumber" : "344"},
      ]} , 
    { "name" : "Ina", "id" : "002", 
      "cases" : [
        {"id" : "532", "casenumber" : "234"},
        {"id" : "734", "casenumber" : "346"},
      ]} ,
    { "name" : "Ora", "id" : "003", 
      "cases" : [
        {"id" : "235", "casenumber" : "974"},
        {"id" : "458", "casenumber" : "125"},
      ]}
    ] 
  }
  ngOnInit(){
    console.log(this.members);
  }
}

Answer 1

你的頂級迭代是錯誤的，你要迭代的數組是在members.members ，所以它應該是：

  <div *ngFor="let mem of members.members"> // here
    {{mem.id}}
    <div class="card-container">
      <div *ngFor="let case of mem.cases">
        {{case.id}}
      </div>
    </div>
  </div>

Answer 2

你遍歷一個objet而不是一個數組，所以你應該通過以下方式指向該數組：

  <div *ngFor="let mem of members.members"> 

Answer 3

更改

<div *ngFor="let mem of members">

至

<div *ngFor="let mem of members.members">