Angular pipe and directive for type casting template variables.
npm install ng-asng-as
bash
npm i ng-as
`
Step 2: usage
type casting template variables with directive eg.:
`ts
import { Component } from '@angular/core';
import { NgAsDirective } from 'ng-as';
// your interface, but also work with any typescript type (class, type, etc.)
interface Person {
name: string;
}
@Component({
selector: 'app-root',
imports: [NgAsDirective],
template:
,
})
export class AppComponent {
// NOTE: If you have "strictPropertyInitialization" enabled,
// you will need to add a non-null assertion (!)
public Person!: Person; // publish your interface into html template
person: Person = { name: 'Simone' }; // the data
}
`
type casting template variables with pipe eg.:
`ts
import { Component } from '@angular/core';
import { NgAsPipe } from 'ng-as';
// your interface, but also work with any typescript type (class, type, etc.)
interface Person {
name: string;
}
@Component({
selector: 'app-root',
imports: [NgAsPipe],
template:
,
})
export class AppComponent {
// NOTE: If you have "strictPropertyInitialization" enabled,
// you will need to add a non-null assertion (!)
public Person!: Person; // publish your interface into html template
person: Person = { name: 'Simone' }; // the data
}
`
$3
!alt text
Example: MatTable
matCellDef cannot infer the type of its parent's input. But with ng-as you can strong-type its template variable.
`ts
import { Component } from '@angular/core';
import {MatTableModule} from '@angular/material/table';
import { NgAsPipe } from 'ng-as';
export interface PeriodicElement {
name: string;
position: number;
weight: number;
symbol: string;
}
const ELEMENT_DATA: PeriodicElement[] = [
{position: 1, name: 'Hydrogen', weight: 1.0079, symbol: 'H'},
{position: 2, name: 'Helium', weight: 4.0026, symbol: 'He'},
{position: 3, name: 'Lithium', weight: 6.941, symbol: 'Li'},
{position: 4, name: 'Beryllium', weight: 9.0122, symbol: 'Be'},
{position: 5, name: 'Boron', weight: 10.811, symbol: 'B'},
{position: 6, name: 'Carbon', weight: 12.0107, symbol: 'C'},
{position: 7, name: 'Nitrogen', weight: 14.0067, symbol: 'N'},
{position: 8, name: 'Oxygen', weight: 15.9994, symbol: 'O'},
{position: 9, name: 'Fluorine', weight: 18.9984, symbol: 'F'},
{position: 10, name: 'Neon', weight: 20.1797, symbol: 'Ne'},
];
@Component({
selector: 'table-basic-example',
imports: [NgAsPipe, MatTableModule],
template:
| No. | {{(element | as: PeriodicElement).position}} | Name | {{(element | as: PeriodicElement).name}} | Weight | {{(element | as: PeriodicElement).weight}} | Symbol | {{(element | as: PeriodicElement).symbol}} |
|---|
,
})
export class TableBasicExample {
PeriodicElement!: PeriodicElement;
displayedColumns: string[] = ['position', 'name', 'weight', 'symbol'];
dataSource = ELEMENT_DATA;
}
``