将输入类型号限制为角度2中的小数点后两位 [英] limit input type number to 2 place of decimal in angular 2

问题描述

我在html页面上有许多输入框.我想限制用户在小数点后2位后不能输入任何数字.

I have a number of input boxes on a html page. I want to restrict the user from entering any numbers after 2 decimals.

当前尝试应用html 5输入Step ="0.00"，但不起作用.

Currently try to apply html 5 input Step="0.00" but doesn't work.

任何打字稿解决方案都还可以

Any typescript solution is also ok

推荐答案

我使用@pipe

import { Directive,Input,Inject, HostListener, ElementRef, OnInit } from "@angular/core";


const PADDING = "000000";

@Pipe({ name: "CurrencyPipe" })
export class CurrencyPipe implements PipeTransform {
  transform(value: any, args: string[]): any {
     var clean = value.replace(/[^-0-9\.]/g, '');
    var negativeCheck = clean.split('-');
    var decimalCheck = clean.split('.');

     if (negativeCheck[1] != undefined) {
                        negativeCheck[1] = negativeCheck[1].slice(0, negativeCheck[1].length);
                        clean = negativeCheck[0] + '-' + negativeCheck[1];
                        if (negativeCheck[0].length > 0) {
                            clean = negativeCheck[0];
                        }

                    }
        if (decimalCheck[1] != undefined) {
                        decimalCheck[1] = decimalCheck[1].slice(0, 2);
                        clean = decimalCheck[0] + '.' + decimalCheck[1];
                    }

    return clean;
  }

  parse(value: string, fractionSize: number = 2): string {

     var clean = value.replace(/[^-0-9\.]/g, '');
    var negativeCheck = clean.split('-');
    var decimalCheck = clean.split('.');

     if (negativeCheck[1] != undefined) {
                        negativeCheck[1] = negativeCheck[1].slice(0, negativeCheck[1].length);
                        clean = negativeCheck[0] + '-' + negativeCheck[1];
                        if (negativeCheck[0].length > 0) {
                            clean = negativeCheck[0];
                        }

                    }
        if (decimalCheck[1] != undefined) {
                        decimalCheck[1] = decimalCheck[1].slice(0, 2);
                        clean = decimalCheck[0] + '.' + decimalCheck[1];
                    }

    return clean;
  }

}

并且管道在我的指令中扩展.

And Pipe Extends in my directive.

import { Directive, Input, Inject, HostListener, OnChanges, ElementRef, Renderer, AfterViewInit, OnInit } from "@angular/core";
import { CurrencyPipe } from '../../shared/pipe/orderby';

@Directive({ selector: "[CurrencyFormatter]" })
export class CurrencyFormatterDirective {

  private el: HTMLInputElement;

  constructor(
    private elementRef: ElementRef,
    private currencyPipe: CurrencyPipe
  ) {
    this.el = this.elementRef.nativeElement;
  }

  ngOnInit() {
    this.el.value = this.currencyPipe.parse(this.el.value);
  }

  @HostListener("focus", ["$event.target.value"])
  onFocus(value) {
    this.el.value = this.currencyPipe.parse(value); // opossite of transform
  }

  @HostListener("blur", ["$event.target.value"])
  onBlur(value) {
    this.el.value = this.currencyPipe.parse(value);
  }

  @HostListener("keyup", ["$event.target.value"]) 
  onKeyUp(value) {
    this.el.value = this.currencyPipe.parse(value);
  }



}

在组件上导入指令

import { CurrencyFormatterDirective } from '../../shared/directive/showOnRowHover';
import { CurrencyPipe } from '../../shared/pipe/orderby';
providers: [CurrencyPipe,
          CurrencyFormatterDirective]

在您的html输入上输入指令

And Directive on your html Input

 <input type="text"  [(ngModel)]="invoiceDetail.InvoiceAmount" class="form-control"  placeholder="Enter invoice amount"
          CurrencyFormatter>

这篇关于将输入类型号限制为角度2中的小数点后两位的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！