Block Round Off using decimal pipe in angular 4

问题:

Using angular 4,

{{31.94 | number:'1.0-0'}} 

Output: 32

Any idea, how to block the round off. Expecting the result is 31

回答1:

You need to create your custom pipe as DecimalPipe doesn't provide any floor feature. Plus you can add your decimal pipe in it. Your Custom Pipe:

@Pipe({name: 'floor'})
export class FloorPipe implements PipeTransform {
    /**
     *
     * @param value
     * @returns {number}
     */
    transform(value: number): number {
        return Math.floor(value);
    }
}

Use in template as:

  <span>{{ yournumber | floor | your_decimal_pipe }}</span>

回答2:

your.component.ts

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


@Pipe({name: 'DecimalPipe'})
export class NumNotRoundPipe implements PipeTransform {
  transform(value: number): number {
    var num1 = Math.floor(value * 100) / 100;
    return num1;
  }
}

your.module.ts

import {NumNotRoundPipe} from './your.component'

@NgModule({
    imports: [
    ],
    declarations: [
        NumNotRoundPipe
    ],
    entryComponents: [

    ],
    providers: [

    ],
    schemas: [CUSTOM_ELEMENTS_SCHEMA]
})

your.component.html

<span>{{yourNumber | DecimalPipe:'1.2-2'}}</span>

回答3:

You might not need an extra custom pipe. Output is a string and there are plenty of string pipes. You might truncate like this :

{{31.94 | slice:0:2}}
//Output : 31

Would achieve your desired output in that specific case.

{{1.94 | number:'2.2-2' | slice:0:2}}
//Output : 01

You'll still want to use custom pipe for now if you don't want padding 0.