angular2不能在一个元素上绑定多个模板
angular2 Can't have multiple template bindings on one element
我有这个angular2模板:
<template *ngIf="alerts.length > 0">
<alert *ngFor="let alert of alerts;let i = index" [type]="alert.type" dismissible="true" (close)="closeAlert(i)">
{{ alert?.msg }}
</alert>
</template>
我得到这些错误:
zone.js:461 Unhandled Promise rejection: Template parse errors:
Can't have multiple template bindings on one element. Use only one attribute named 'template' or prefixed with * (" </div>
<div *ngSwitchCase="false" class="container p-t-10">
<alert *ngIf="alerts.length > 0" [ERROR ->]*ngFor="let alert of alerts;let i = index" [type]="alert.type" dismissible="true" (close)="closeAlert"): b@5:37
我把*ngIf和*ngFor放在不同的html元素。这应该行得通。没有?
:
Can't bind to 'type' since it isn't a known property of 'alert'. (""container p-t-10">
<alert *ngIf="alerts.length > 0" *ngFor="let alert of alerts;let i = index" [ERROR ->][type]="alert.type" dismissible="true" (close)="closeAlert(i)">
{{ alert?.msg }}
</alert>
"): b@5:80
我添加了
*ngIf="alerts.length > 0
以避免alert = []
的发生。不然我怎么修呢?
*ngFor
中的*
使Angular添加了一个<template>
标签。在<template>
标签上,这是没有意义的,因此这里的结构指令有不同的语法。
<template ngFor [ngForOf]="alerts" let-alert let-i="index">
由于在不同的地方几乎相同的语法不同会造成相当大的混乱,Angular团队最近引入了
<ng-container>
的行为类似于<template>
标记(没有添加到DOM),但允许更常见的语法
<ng-container *ngIf="alerts.length > 0">
<alert *ngFor="let alert of alerts;let i = index" [type]="alert.type" dismissible="true" (close)="closeAlert(i)">
{{ alert?.msg }}
</alert>
</ng-container>
在这种情况下应该使用<ng-container>
。例如:
<ng-container *ngIf="totalItems > 0">
<tr *ngFor="let item of outputs| paginate: { id:'ab', itemsPerPage: pageSize, currentPage: currentPage, totalItems: totalItems }; let $index = index">
<td>{{item.x}}</td>
<td>{{item.y | date: 'MMMM d, y, h:mm:ss a' }}</td>
<td>{{item.z}}</td>
<td>{{item.r}}</td>
</tr>
</ng-container>
<ng-container *ngIf="totalItems > 10">
<tr *ngFor="let item of outputs| paginate: { id:'aabbbbbbbbb', itemsPerPage: pageSize, currentPage: currentPage, totalItems: totalItems }; let $index = index">
<td>{{item.x}}</td>
<td>{{item.y | date: 'MMMM d, y, h:mm:ss a' }}</td>
<td>{{item.z}}</td>
<td>{{item.r}}</td>
</tr>
</ng-container>