动态ngTemplateOutlet值

Question

有没有办法动态设置*ngTemplateOutlet指令的值？

一些类似的东西：

<div *ngFor="let item of [ 'div', 'span' ]">
  <ng-container *ngTemplateOutlet="{{ item }}"></ng-container>
</div>

<ng-template #div>
  <div>some text inside a div</div>
</ng-template>

<ng-template #span>
  <span>some text inside a span</span>
</ng-template>

Answer 1

只需将TemplateRef变量指向ngTemplateOutlet即可

在HTML中：

<button (click)="toggleTemplateSelected()">Toggle Template</button>
<br />
<p>Showing 
  <span class='viewType' *ngIf="showViewTemplate">C</span>
  <span class='viewType' *ngIf="!showViewTemplate">C2</span> 
  template:</p>
<ng-container *ngTemplateOutlet='liveTemplate'></ng-container>

<!--Templates: -->
<ng-template #tmplC>
  Hello from TemplateC
</ng-template>

<ng-template #tmplC2>
  Hello from TemplateC2
</ng-template>

在代码中：

@ViewChild('tmplC') tmplC: TemplateRef<any>;
@ViewChild('tmplC2') tmplC2: TemplateRef<any>;

showViewTemplate = true;
liveTemplate: TemplateRef<any>;

toggleTemplateSelected() {
    this.showViewTemplate = !this.showViewTemplate;
    this.liveTemplate = this.showViewTemplate ? this.tmplC : this.tmplC2;
}

您还可以将ngTemplateOutlet指向一个返回TemplateRef的函数。

Answer 2

以下是最短且最佳可行的解决方案

1创建指令"dynamic-template.directive.ts"

import { Directive, Input, TemplateRef } from '@angular/core';
@Directive({
  selector: '[dynamic-template]'
})
export class DynamicTemplateDirective {
  @Input() id: number;
  constructor(public template: TemplateRef<any>) { }
}  

Content2在组件帮助器中定义动态模板--compleent.html

<ng-template [dynamic-template] [id]="1">
  This is 1st Template
</ng-template>
<ng-template [dynamic-template] [id]="2">
  This is 2nd Template
</ng-template>
<ng-template [dynamic-template] [id]="3">
  This is 3rd Template
</ng-template>

Content3在您的组件帮助器中使用动态模板--Content.Component.ts

import { DynamicTemplateDirective } from '@app/components/dynamic-template.directive';

export class HelperContentComponent implements OnInit {
helpTemplate: TemplateRef<any>;
  @ViewChildren(DynamicTemplateDirective) templateRefs: QueryList<DynamicTemplateDirective>;

constructor(private eventService: EventEmitterService) {
  }

getTemplate(templateId: number): TemplateRef<any> {
    return this.templateRefs.toArray().find(x => x.id == templateId).template;
  }

showHelperContent(id: number) {
    
      this.helpTemplate = this.getTemplate(id);
      
     }
}

在helper-content.component.html中使用4的helpTemplate变量

<div class="content" >
      <ng-container *ngTemplateOutlet="helpTemplate"></ng-container>
    </div>

Answer 3

将项括在圆括号中，使其作为表达式进行计算。*ngTemplateOutlet="(item.ref)"如果不起作用，执行let item of [ { ref: 'div' }, { ref: 'span'} ]并使用类似于Can't get ngTemplateOutlet to work的*ngTemplateOutlet="item.ref"