Typescript 无法使用注入服务
将简单服务导入login.component.ts:`Typescript 无法使用注入服务,typescript,angular,Typescript,Angular,将简单服务导入login.component.ts:` import { Component } from '@angular/core'; import {TestService} from '../login/TestService'; @Component({ providers: [TestService], templateUrl: './app/login/loginTemplate.html' }) export class loginComponent {
import { Component } from '@angular/core';
import {TestService} from '../login/TestService';
@Component({
providers: [TestService],
templateUrl: './app/login/loginTemplate.html'
})
export class loginComponent {
constructor(testService: TestService){}
sendLoginRequest() {
this.testService.writeLine();
}
}
这是TestService文件
import { Injectable } from '@angular/core';
@Injectable ()
export class TestService {
constructor () {}
writeLine () {
return console.log("works from service");
}
}
对于这种简短形式,需要使用
私有
或公共
constructor(private testService: TestService){}
如果没有此访问修饰符,则需要执行以下操作
testService;TestService;
constructor(testService: TestService){
this.testService = testService;
}
错误是什么?真正的问题是什么?