angular - 在打字稿中使用变量，角度

Question

我敢肯定这是一个愚蠢的问题，但我是这种语言的新手，而且我肯定错过了一些东西。我只想执行这段代码：

.ts

import { Component, OnInit } from '@angular/core';
import { Provider } from '../shared/provider.module.ts';
import { Testcase } from '../shared/testcase.module.ts';

@Component({
  selector: 'app-single-test',
  templateUrl: './single-test.component.html',
  styleUrls: ['./single-test.component.scss']
})
export class SingleTestComponent implements OnInit {

  a: int = 2;
  b: int = 3;
  c: int = a*b; 
  
  constructor() { }

  ngOnInit(): void {

  }

}

.html

<div>{{c}}</div>

但在控制台上我收到此错误：

``` ERROR ReferenceError: a is not defined   
    at new SingleTestComponent (main.js:89)
    at NodeInjectorFactory.SingleTestComponent_Factory [as factory] (main.js:105)
    at getNodeInjectable (vendor.js:14920)
    at instantiateAllDirectives (vendor.js:18838)
    at createDirectivesInstances (vendor.js:18212)
    at ɵɵelementStart (vendor.js:25536)
    at Module.ɵɵelement (vendor.js:25587)
    at AppComponent_Template (main.js:181)
    at executeTemplate (vendor.js:18185)
    at renderView (vendor.js:17994)```

what am I missing?

标签： angulartypescript

Answer 1

import { Component, OnInit } from '@angular/core';
import { Provider } from '../shared/provider.module.ts';
import { Testcase } from '../shared/testcase.module.ts';

@Component({
  selector: 'app-single-test',
  templateUrl: './single-test.component.html',
  styleUrls: ['./single-test.component.scss']
})
export class SingleTestComponent implements OnInit {

  a = 2;
  b = 3;
  c = this.a * this.b;  
  
  constructor() { }

  ngOnInit(): void {

  }

}