Typescript 为什么不能使用$EVENT接收字符串数组

您已将事件emits 器设置为字符串，但您正在emits 一个令人困惑的对象.因此，我将代码转换为发出数组，而不是对象.

emitResult(): void {
    this.onNewresult.emit([...this.screenValues]);
}

我们可以将事件onNewResult参数更改为string[]，这将解决问题！

onNewresult(data: string[]): void {
    console.log(data);
}  

下面是工作示例.

children

import { Component, EventEmitter, Output } from '@angular/core';
import { FormsModule } from '@angular/forms';

@Component({
  selector: 'app-calculator',
  standalone: true,
  imports: [FormsModule],
  template: `
    <input type="text" [(ngModel)]="value"/>
    <button (click)="operaciones()">operaciones</button>
  `,
})
export class CalculatorComponent {
  value = '';
  public firstRow: string[] = ['7', '8', '9', '+', '='];
  public secondRow: string[] = ['4', '5', '6', '*', '/'];
  public thirdRow: string[] = ['1', '2', '3', '-', 'AC'];
  public fourthRow: string[] = ['0', '.', '(', ')'];
  @Output()
  public onNewresult: EventEmitter<string[]> = new EventEmitter<string[]>();
  public screenValues: string[] = [];
  apagar(): void {
    console.log('Apagado');
    this.value = '';
  }
  operaciones(): void {
    let pantallaValue = this.value;
    this.screenValues.unshift(pantallaValue); //añado el valor de la operacion al princio del array
    let operacion: number = eval(pantallaValue); //eval trasfoma una cadena en una operacion matematica
    pantallaValue = operacion.toString();
    this.screenValues[0] += '= ' + pantallaValue;
    this.emitResult();
    //usar services para pasar datos desde buttons hasta screen
  }

  monitor(index: string): void {
    let pantalla = document.getElementById('pantalla') as HTMLInputElement;
    pantalla.value += index;
  }
  emitResult(): void {
    this.onNewresult.emit([...this.screenValues]);
  }
}

亲本

import { Component, EventEmitter, Output } from '@angular/core';
import { FormsModule } from '@angular/forms';
import { bootstrapApplication } from '@angular/platform-browser';
import 'zone.js';
import { CalculatorComponent } from './calculator/calculator.component';

@Component({
  selector: 'app-root',
  standalone: true,
  imports: [FormsModule, CalculatorComponent],
  template: `
    <app-calculator (onNewresult)="onNewresult($event)"/>
  `,
})
export class App {
  onNewresult(data: string[]) {
    console.log(data);
  }
}

bootstrapApplication(App);

stackblitz个