Angular 6 - ERROR TypeError: "this.router is undefined"

user_9687794 0
Viewed 3702

Well, here i go again with more Angular problems. Sorry (?)

The thing is that i'm trying to redirect the user after a registration but for some reason, i'm getting the next error everytime:

ERROR TypeError: "this.router is undefined"

Basically, i'm handling the form submit (which works fine) inputs and posting them to my Laravel API, which takes it, executes the registration and returns a success message. Either way, i can't redirect the user (using Angular Router) using the next piece of code:

onSubmit() {
    this.authService.registerUser(this.user).subscribe(
      response => {
        let data = Object.assign(response.alert, this.denyControllConfig);
        this.sweetAlert(data);
      },
      error => {
        let data = {};
        let errors = error.error.errors;
        for (let key in errors) data[key] = errors[key][0];
        // this.sweetAlert(data);
      }
    );
    setTimeout(function () {
      this.router.navigate(['login']);
    }, 2000);
  }

I have imported the Rourter like this in the top of my file:

import { Router } from "@angular/router";

And this is my class constructor:

constructor(
    private router: Router,
    private authService: AuthService
  ) { }

Is there anything wrong with it ?

angular6 angular
3 Answers

You need to use arrow functions in your code to be able to use the this

setTimeout(() => {
    this.router.navigate(['login']);
}, 2000);
user_102576110

I believe the problem is in the following code:

setTimeout(function () {
  this.router.navigate(['login']);
}, 2000);

In this case, since you are using anonymous function, the this keyword is the context of the function itself. To fix this, change it to:

setTimeout(() => {
   this.router.navigate(['login']);
})

The way arrow functions work, will allow this to be the class context instead of the function context.

user_43574090

Your setTimeout must use an arrow function as the callback to avoid re-binding the context of this.

user_33210160
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