Angular利用内容投射向组件输入ngForOf模板的方法,angularngforof88bf必发娱乐

现在,我们写一个组件puppiesListCmp,用于显示小狗狗的列表:

Angular利用内容投射向组件输入ngForOf模板的方法,angularngforof

现在,我们写一个组件puppiesListCmp,用于显示小狗狗的列表:

//puppies-list.component.ts
@Component({
 selector: 'puppies-list',
 template: `
  <div *ngFor="let puppy of puppies">
   {{puppy.name}}
   {{puppy.age}}
   {{puppy.color}}
  </div>
`
})
export class puppiesListCmp{
 @Input() puppies: Puppy[];
}
interface Puppy {
 name: string,
 age: number,
 color: string
}

然后这样使用:

//app.component.ts
@Component({
 selector: 'my-app',
 template: `
  <puppies-list [puppies]="puppies"></puppies-list>
`
})
export class App{
 puppies = [
  {
   name: "sam",
   age: 0.6,
   color: "yellow"
  },
  {
   name: "bingo",
   age: 1.5,
   color: "black"
  }
 ]
}

效果就行这样:

88bf必发娱乐 1

但是,我希望我们的puppiesListCmp组件可以满足不同的需求,比如在数据不变的情况下只显示小狗狗的name和color,就像这样:

88bf必发娱乐 2

这就是本文的重点了。我们需要实现用户自定义模板!

现在我们不写死组件的模板了,而是让用户从外部输入!

首先,我们的组件模板:

<div *ngFor="let puppy of puppies">
   {{puppy.name}}
   {{puppy.age}}
   {{puppy.color}}
</div>

等价于:

<ng-template ngFor let-puppy [ngForOf]="puppies">
   <div>
    {{puppy.name}}
    {{puppy.age}}
    {{puppy.color}}
   </div>
</ng-template>

然后,用@ContentChild(关于@ContentChild可以查看这里,需FQ)获取到外部(相对puppiesListCmp组件而言)自定义模板,并赋给ngForTemplate。也就是说,这部分:

<div>
  {{puppy.name}}
  {{puppy.age}}
  {{puppy.color}}
</div>

不再像之前那样写死在组件里了,而是由使用者在父组件中自定义,然后利用Angular的内容投射(Content
Projection),投射到puppiesListCmp组件里面。就像这样:

//puppies-list.component.ts
import { Component, Input, ContentChild, TemplateRef } from '@angular/core';
import { NgForOfContext } from '@angular/common';
@Component({
 selector: 'puppies-list',
 template: `
<ng-template ngFor let-puppy [ngForOf]="puppies" [ngForTemplate]="tpl"></ng-template>
`
})
export class puppiesListCmp{
 @Input() puppies: Puppy[];
 @ContentChild(TemplateRef) tpl: TemplateRef<NgForOfContext<Puppy>>
}
interface Puppy {
 name: string,
 age: number,
 color: string
}

这样我们的组件就算完成了。然后我们使用它:

//app.component.ts
@Component({
 selector: 'my-app',
 template: `
<puppies-list [puppies]="puppies">
 <ng-template let-puppy>
  <div>
   {{puppy.name}}
   {{puppy.age}}
   {{puppy.color}}
  </div>
 </ng-template>
</puppies-list>
`
})

效果还是一样的:

88bf必发娱乐 3

如果我们只要显示小狗狗的name和color,只要这样写就好了:

//app.component.ts
@Component({
 selector: 'my-app',
 template: `
<puppies-list [puppies]="puppies">
 <ng-template let-puppy>
  <div>
   {{puppy.name}}
   {{puppy.color}}
  </div>
 </ng-template>
</puppies-list>
`
})

效果就像这样:

88bf必发娱乐 4

这样的组件很灵活,想要什么样的效果都可以定制,这就实现了组件的复用。

好了,本文就到此为止了。不当之处,欢迎指出!希望对大家的学习有所帮助,也希望大家多多支持帮客之家。

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现在,我们写一个组件puppiesListCmp,用于显示小狗狗的列表:
//puppies-list.comp…

//puppies-list.component.ts
@Component({
 selector: 'puppies-list',
 template: `
  <div *ngFor="let puppy of puppies">
   {{puppy.name}}
   {{puppy.age}}
   {{puppy.color}}
  </div>
`
})
export class puppiesListCmp{
 @Input() puppies: Puppy[];
}
interface Puppy {
 name: string,
 age: number,
 color: string
}

然后这样使用:

//app.component.ts
@Component({
 selector: 'my-app',
 template: `
  <puppies-list [puppies]="puppies"></puppies-list>
`
})
export class App{
 puppies = [
  {
   name: "sam",
   age: 0.6,
   color: "yellow"
  },
  {
   name: "bingo",
   age: 1.5,
   color: "black"
  }
 ]
}

效果就行这样:

88bf必发娱乐 5

但是,我希望我们的puppiesListCmp组件可以满足不同的需求,比如在数据不变的情况下只显示小狗狗的name和color,就像这样:

88bf必发娱乐 6

这就是本文的重点了。我们需要实现用户自定义模板!

88bf必发娱乐,现在我们不写死组件的模板了,而是让用户从外部输入!

首先,我们的组件模板:

<div *ngFor="let puppy of puppies">
   {{puppy.name}}
   {{puppy.age}}
   {{puppy.color}}
</div>

等价于:

<ng-template ngFor let-puppy [ngForOf]="puppies">
   <div>
    {{puppy.name}}
    {{puppy.age}}
    {{puppy.color}}
   </div>
</ng-template>

然后,用@ContentChild(关于@ContentChild可以查看这里,需FQ)获取到外部(相对puppiesListCmp组件而言)自定义模板,并赋给ngForTemplate。也就是说,这部分:

<div>
  {{puppy.name}}
  {{puppy.age}}
  {{puppy.color}}
</div>

不再像之前那样写死在组件里了,而是由使用者在父组件中自定义,然后利用Angular的内容投射(Content
Projection),投射到puppiesListCmp组件里面。就像这样:

//puppies-list.component.ts
import { Component, Input, ContentChild, TemplateRef } from '@angular/core';
import { NgForOfContext } from '@angular/common';
@Component({
 selector: 'puppies-list',
 template: `
<ng-template ngFor let-puppy [ngForOf]="puppies" [ngForTemplate]="tpl"></ng-template>
`
})
export class puppiesListCmp{
 @Input() puppies: Puppy[];
 @ContentChild(TemplateRef) tpl: TemplateRef<NgForOfContext<Puppy>>
}
interface Puppy {
 name: string,
 age: number,
 color: string
}

这样我们的组件就算完成了。然后我们使用它:

//app.component.ts
@Component({
 selector: 'my-app',
 template: `
<puppies-list [puppies]="puppies">
 <ng-template let-puppy>
  <div>
   {{puppy.name}}
   {{puppy.age}}
   {{puppy.color}}
  </div>
 </ng-template>
</puppies-list>
`
})

效果还是一样的:

88bf必发娱乐 7

如果我们只要显示小狗狗的name和color,只要这样写就好了:

//app.component.ts
@Component({
 selector: 'my-app',
 template: `
<puppies-list [puppies]="puppies">
 <ng-template let-puppy>
  <div>
   {{puppy.name}}
   {{puppy.color}}
  </div>
 </ng-template>
</puppies-list>
`
})

效果就像这样:

88bf必发娱乐 8

这样的组件很灵活,想要什么样的效果都可以定制,这就实现了组件的复用。

好了,本文就到此为止了。不当之处,欢迎指出!希望对大家的学习有所帮助,也希望大家多多支持脚本之家。