W3cubDocs

/Angular 7

PipeTransform

interface

To create a Pipe, you must implement this interface.

See more...

interface PipeTransform {
  transform(value: any, ...args: any[]): any
}

Description

Angular invokes the transform method with the value of a binding as the first argument, and any parameters as the second argument in list form.

Methods

transform(value: any, ...args: any[]): any

Parameters
value any
args any[]
Returns

any

Usage notes

Example

The RepeatPipe below repeats the value as many times as indicated by the first argument:

import {Pipe, PipeTransform} from '@angular/core';

@Pipe({name: 'repeat'})
export class RepeatPipe implements PipeTransform {
  transform(value: any, times: number) {
    return value.repeat(times);
  }
}

Invoking {{ 'ok' | repeat:3 }} in a template produces okokok.

© 2010–2019 Google, Inc.
Licensed under the Creative Commons Attribution License 4.0.
https://v7.angular.io/api/core/PipeTransform