Resolve the problem in Angular 6 related to an unused type and the absence of a certain property

I recently watched a video tutorial (link: https://www.youtube.com/watch?v=z4JUm0Bq9AM) and encountered some errors in my CLI. The specific errors are as follows:

  1. ERROR in sidebar.component.ts(12,5): error TS7028: Unused label.
  2. sidebar.component.ts(14,56): error TS2339: Property 'currentUrl' does not exist on type 'SidebarComponent'.

The section of code that is causing the errors is shown below:

  constructor(private router: Router) {
    currentUrl: String;

    router.events.subscribe((_: NavigationEnd) => this.currentUrl = _.url)
  }

In the tutorial, from timestamp 48:14 to 49:18, the presenter did not encounter any errors with this exact code. However, when I tried it in Visual Studio Code, both instances of `currentURL` were underlined. I am struggling to understand why this discrepancy exists and how to resolve it.

One difference I noticed between our codes is that I used uppercase 'String' instead of 'string', which actually led to a different error initially.

If anyone can provide insight into this issue, it would be greatly appreciated. Thank you!

angulartypescript

Answer №1

Check out this accurate code snippet:

export class SidebarComponent {
  currentLink: String;
  constructor(private navigation: Router) {
    navigation.events.subscribe((_: NavigationEnd) => this.currentLink = _.url)
  }
}

Even though I can't view the video, if your statement holds true, then you should celebrate because your linter settings seem to be superior to his!

Answer №2

Declare the currentUrl variable before the constructor is called

currentUrl: String;
constructor(private router: Router) {

  router.events.subscribe((_: NavigationEnd) => this.currentUrl = _.url)
}

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