Apply existing pipe in a custom pipe [duplicate]

Question

I have a Precision Pipe that gives me the desired precision number... However, that pipe does not use any other number formatting, like local thousand separator etc.

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

@Pipe({ name: 'precision' })
export class PrecisionPipe implements PipeTransform {
  transform(value: number | string, precision: number): string {
    return typeof value === 'number' ? value.toFixed(precision) : value;
  }
}

Is there a way to apply the 'number' pipe in my Precision pipe, to localize it?

Knowing that

> 444444.5.toFixed(2)
'444444.50'

// I need "444 444.50"

Ferryboat

Answer 1

A possibility is to use the consecutive pipes in HTML

<div>{{ myNumber | precision:myPrecision | number }}</div>

If not, I tried the DecimalPipe inside my PrecisionPipe:

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

@Pipe({ name: 'precision' })
export class PrecisionPipe implements PipeTransform {
  transform(
    value: number | string,
    precision: number,
    locale?: string | undefined,
    digitsInfo?: string | undefined,
  ): string | number | null {

    let pipe = new DecimalPipe(locale ?? "en");
    return isFinite(+value) ?
      pipe.transform((+value).toFixed(precision), digitsInfo, locale)
      : value;
  }
}

The only "problem" is that that last option asks you to explicitly set the current language in the pipe...

Ferryboat

Normally you should be able to inject the DecimalPipe in the PrecisionPipe through the constructor. – Breath