What is the best way to extract value from subscribing?

I attempted to accomplish this task, however, I am encountering issues. Any assistance you can provide would be greatly appreciated! Thank you!

    export class OuterClass {
    let isUrlValid = (url:string) => {
            let validity:boolean
            this.http.get(url).subscribe((result) => {
                  validity = Object.keys(result).length > 0;
                });
            return validity;
          }
     }

Answer №1

Instead of directly assigning the function to isEffectiveUrl, you should create a local variable and execute your http.get within a function or lifecycle hook.

For example:

export class DataFetcher {

  isUrlValid: boolean = false;

  checkUrlValidity(url: string): void {
    this.http.get(url).subscribe((response) => {
      this.isUrlValid = Object.keys(response).length > 0;
    });
  }

}

Keep in mind that this approach follows a reactive model, meaning the code inside the subscribe block runs asynchronously.

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