在输入时将参数传递给 Angular 4 指令 [英] Pass parameter to Angular 4 directive on input

问题描述

我有一个这样的输入文本字段

I have an input text field like this

<input type="text" class="form-control"  [inputTextFilter]="A" [ngModel]="name">

我的指令是:

import { Directive, Input, HostListener } from '@angular/core';

@Directive({
  selector: '[inputTextFilter]'
})

export class InputTextFilterDirective {
  @Input('inputTextFilter') params: string;

  @HostListener('keypress', ['$event'])
  onKeyUp(event: KeyboardEvent) {
    console.log('got parameters: '+this.params);
  }
}

并且我创建了一个名为inputTextFilter"的指令，我想将A"参数传递给它.我传递的参数总是显示为未定义.

and I have created a Directive called "inputTextFilter" to which I want to pass the "A" parameter. My passed parameter always shows as undefined.

推荐答案

试试这个.

import {Directive, SimpleChanges} from '@angular/core';

@Directive({
  selector: '[inputTextFilter]'
})
export class MyDirective {
  @Input('inputTextFilter') params: string;
  constructor(){}
  ngOnInit(){
     console.log(this.params)
  }
}

这篇关于在输入时将参数传递给 Angular 4 指令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！