Question

我正在尝试将服务用作指令的一般用途，而不是组件。但它抱怨它没有在儿童指令中获得服务。我希望在指令中使用该服务：

// CurrentTimeService.ts
import { Injectable } from '@angular/core'

@Injectable()
export class CurrentTimeService {
  dt: number;

  constructor() {
    this.dt = new Date().getTime();
  }


}

app.ts
//our root app component
import {Component} from '@angular/core'
import {CurrentTimeService} from "./CurrentTimeService"
import {SimpleDirective} from "./SimpleDirective"

@Component({
  selector: 'my-app',
  providers: [CurrentTimeService],
  template: `
    <div>
      <h2 mySimpleDirective>Hello {{name}}</h2>

    </div>
  `,
  directives: [SimpleDirective]
})
export class App {
  constructor() {
    this.name = 'Angular2 (Release Candidate!)'
  }
}

SimpleDirective.ts
import {Directive} from '@angular/core';
import { CurrentTimeService  } from "./currentTimeService"

@Directive({
    selector: '[mySimpleDirective]'
})
export class SimpleDirective {
  constructor(private currentTimeService: CurrentTimeService) {


  }

  /*
  uncomment this command, it is working because it doesn't demand the service
  constructor() { }
  */

}

你可以检查一下整个程序：https://plnkr.co/edit/s0zUkI?p=preview

提前致谢

Answer 1

SimpleDirective.ts中有一个错误的#include <iostream> struct Foo : std::ofstream {}; template <typename T> Foo& operator<<(Foo& strm, const T& var) { std::cout << "X" << std::endl; return strm; }; int main() { Foo oac; oac << std::endl; }语句。改变这个

import

到

import { CurrentTimeService  } from "./currentTimeService"

Plunker example

是否可以在角度2中的子指令中使用父提供程序

1 个答案: