离子2:找不到'对象'类型的不同支持对象'[object Object]'。 NgFor仅支持绑定到诸如Arrays之类的Iterables [英] Ionic 2: Cannot find a differ supporting object '[object Object]' of type 'object'. NgFor only supports binding to Iterables such as Arrays
问题描述
我正在尝试使用以下命令从我的服务类中的firebase检索数据:
I am trying to retrieve data from firebase in my service class using:
return this.http.get('https://myfirstfirebaseproject-6da6c.firebaseio.com/products.json')
.map(res => res.json());
在home.ts中,我使用以下方式订阅:
In home.ts, I then subscribe to it using:
this.productService.fetchProducts()
.subscribe(data => {
console.log(data)
this.products = data;
});
我输出到home.html使用:
I output to home.html using:
<ion-card ion-item *ngFor="let product of products; let i = index" (click)="onItemClick(product)">
<ion-card-header>
{{ product.date | date }}
</ion-card-header>
<ion-card-content>
<ion-card-title>
{{ product.title }}
</ion-card-title>
<p>
{{ product.content }}
</p>
</ion-card-content>
</ion-card>
但我一直收到错误
错误:无法找到'object'类型的不同支持对象'[object Object]'。 NgFor仅支持绑定到Iterables,例如Arrays。
Error: Cannot find a differ supporting object '[object Object]' of type 'object'. NgFor only supports binding to Iterables such as Arrays.
我试着查看类似的问题,但无济于事。请帮助。
I tried looking at similar issues but to no avail. Please help.
推荐答案
请检查您的JSON。 https://myfirstfirebaseproject-6da6c.firebaseio.com/products.json
它返回一个Object而不是一个Array。这就是为什么你不能在ngFor中使用返回的数据。
Please check your JSON. https://myfirstfirebaseproject-6da6c.firebaseio.com/products.json It returns an Object not an Array. That is why you cannot use returned data in ngFor.
{
-KiTWPuI_TYt0b_Qi03Y: {
amount: 0,
category: "Baby",
content: "I love cricket",
date: "2017-03-01",
title: "Cricket"
},
-Kid7fghtlxkyrOChQPk: {
amount: "111",
category: "Book",
content: "updated content",
date: "2017-04-01",
title: "Cycling"
},
d9e7545c-90a3-4a57-97ab-ea3bf9171023: {
amount: "12",
category: "Baby",
content: "COnten1",
date: "2017-01-01",
title: "Title2"
}
}
试试这个:
<ion-card ion-item *ngFor="let key of keys; let i = index" (click)="onItemClick(key)">
<ion-card-header>
{{ products[key].date | date }}
</ion-card-header>
<ion-card-content>
<ion-card-title>
{{ products[key].title }}
</ion-card-title>
<p>
{{ products[key].content }}
</p>
</ion-card-content>
</ion-card>
在你的component.ts中:
In your component.ts:
keys: string[];
...
this.productService.fetchProducts()
.subscribe(data => {
console.log(data)
this.products = data;
this.keys = Object.keys(this.products);
});
并相应地修改你的onItemClick()。
And modify your onItemClick() accordingly.
这篇关于离子2:找不到'对象'类型的不同支持对象'[object Object]'。 NgFor仅支持绑定到诸如Arrays之类的Iterables的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!