How to pass an expression to a component as an input in Angular2?
I need to pass an expression to a component that will be evaluated inside an component's template.
For example, component:
@Component({
selector: 'app-my-component',
...
})
export class MyComponent {
@Input items: MyClass;
@Input expression: String;
...
}
with component's template:
<div *ngFor="let item of items">
{{expression}}
</div>
Usage of MyComponent:
<app-my-component [items]="listOfItems" [expression]="'[item.id] item.name'">
</app-my-component>
As there will be more than one input, I would like to avoid usage of TemplateRef.
Solution 1:
Maybe one of this options can helps you:
1) Using ngForTemplate
input property of NgFor directive:
Component
@Component({
selector: 'app-my-component',
template: `
<div *ngFor="let item of items template: itemTemplate"></div>`
})
export class MyComponent {
@Input() items: any;
@ContentChild(TemplateRef) itemTemplate: TemplateRef<any>;
}
Parent
<app-my-component [items]="listOfItems">
<ng-template let-item>[{{item.id}}] {{item.name}}</ng-template>
</app-my-component>
Plunker
2) Using the NgTemplateOutlet
directive
Component
@Component({
selector: 'app-my-component',
template: `
<div *ngFor="let item of items">
<ng-template [ngTemplateOutlet]="itemTemplate" [ngTemplateOutletContext]="{ $implicit: item }"></ng-template>
</div>`
})
export class MyComponent {
@Input() items: any;
@ContentChild(TemplateRef) itemTemplate: TemplateRef<any>;
}
Parent remains the same:
<app-my-component [items]="listOfItems">
<ng-template let-item>[{{item.id}}] {{item.name}}</ng-template>
</app-my-component>
Plunker
This way inside of <ng-template let-item>...</ng-template>
you can use desired expression