title: Angular: This type is not supported as injection token
body: <p>I am just trying to create a constructor with type number but I am getting the error as 'This type is not supported as injection token'</p>
  <p>I am new to Angular. What am I doing wrong here?</p>
  <pre><code>import { Component } from '@angular/core'
  
  @Component({
      selector : 'app-even',
      templateUrl : './even.component.html',
      styleUrls : ['./even.component.css']
  })
  export class EvenComponent
  {
      num : number;
      
      constructor(num : number){
          this.num = num;
      }
  }
  </code></pre>
  <p>I am getting the below error:</p>
  <p><a href="https://i.stack.imgur.com/FYRzL.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/FYRzL.png" alt="Injection type error" /></a></p>
  <p>I use this EvenComponent in AppComponent</p>
  <pre><code>export class AppComponent implements DoCheck{
    evenCounts : EvenComponent[];
  }
  </code></pre>