Angular 17 Error Handling: What's New and How to Implement It

Angular 17 introduces a number of new features and improvements to the error handling system. In this blog post, we will discuss some of the most important changes, as well as how to implement error handling in your Angular 17 application.

New features in Angular 17 error handling

Here are some of the new features in Angular 17 error handling:

• Improved error handling for HTTP requests. Angular 17 now provides better error handling for HTTP requests. For example, Angular 17 can now automatically retry failed HTTP requests, and it can also provide more detailed error messages to users.
• New global error handler. Angular 17 introduces a new global error handler that is more robust and efficient than the previous global error handler.
• New error logging capabilities. Angular 17 provides new error logging capabilities, such as the ability to log errors to a remote logging service.

How to implement error handling in Angular 17

There are a number of ways to implement error handling in Angular 17. Here are a few tips:

• Use try/catch blocks to handle synchronous errors. Synchronous errors are errors that occur when your application is executing code. To handle synchronous errors, you can use try/catch blocks. If an error occurs inside the try block, the catch block will be executed.
• Use a global error handler to handle uncaught errors. Uncaught errors are errors that occur outside of a try/catch block. To handle uncaught errors, you can use a global error handler. A global error handler is a class that implements the ErrorHandler interface. The default error handler in Angular will log all uncaught errors to the console. However, you can create your own custom global error handler to handle uncaught errors in a more specific way.
• Log all errors. It is important to log all errors that occur in your application, regardless of whether they are handled or not. Logging errors can help you to track down and fix problems more quickly. You can log errors to a variety of destinations, such as the console, a file, or a remote logging service.
• Provide users with clear and concise error messages. When an error occurs in your application, it is important to provide users with a clear and concise error message. The error message should explain what the error is and how the user can resolve it. If possible, the error message should also provide a link to a support page where the user can learn more about the error and how to fix it.

Example of a global error handler in Angular 17

The following code shows a simple example of a global error handler in Angular 17:

import { ErrorHandler, Injectable } from '@angular/core';

@Injectable({
  providedIn: 'root'
})
export class CustomErrorHandler implements ErrorHandler {

  handleError(error: any): void {
    // Log the error to the console.
    console.error(error);

    // Display a friendly error message to the user.
    alert('An unexpected error occurred. Please try again later.');
  }
}

To register your global error handler, you need to add it to the providers array in your root module. The following code shows how to do this:

import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { AppComponent } from './app.component';
import { CustomErrorHandler } from './custom-error-handler.service';

@NgModule({
  declarations: [
    AppComponent
  ],
  imports: [
    BrowserModule
  ],
  providers: [
    CustomErrorHandler,
  ],
  bootstrap: [AppComponent]
})
export class AppModule { }

Once you have registered your global error handler, it will be called whenever an uncaught error occurs in your application. You can use the handleError() method to log the error, display a friendly error message to the user, or take any other necessary actions.

Conclusion

Error handling is an important part of developing any complex software application. By implementing effective error handling in your Angular 17 application, you can ensure that your application remains stable and responsive even when unexpected errors occur.

• Date: 08 Oct 2023