docs: Add example Unhandled errors in Angular documentation (#64356)

SkyZeroZx · AndrewKushnir · commit 7cc6af9ae709 · 2025-10-13T08:30:26.000-07:00
PR Close #64356
diff --git a/adev/src/content/best-practices/error-handling.md b/adev/src/content/best-practices/error-handling.md
@@ -16,13 +16,33 @@ Angular does _not_ catch errors inside of APIs that are called directly by your
 
 Angular catches _asynchronous_ errors from user promises or observables only when:
 
-* There is an explicit contract for Angular to wait for and use the result of the asynchronous operation, and
-* When errors are not presented in the return value or state.
+- There is an explicit contract for Angular to wait for and use the result of the asynchronous operation, and
+- When errors are not presented in the return value or state.
 
 For example, `AsyncPipe` and `PendingTasks.run` forward errors to the `ErrorHandler`, whereas `resource` presents the error in the `status` and `error` properties.
 
 Errors that Angular reports to the `ErrorHandler` are _unexpected_ errors. These errors may be unrecoverable or an indication that the state of the application is corrupted. Applications should provide error handling using `try` blocks or appropriate error handling operators (like `catchError` in RxJS) where the error occurs whenever possible rather than relying on the `ErrorHandler`, which is most frequently and appropriately used only as a mechanism to report potentially fatal errors to the error tracking and logging infrastructure.
 
+```ts
+export class GlobalErrorHandler implements ErrorHandler {
+  private readonly analyticsService = inject(AnalyticsService);
+  private readonly router = inject(Router);
+
+  handleError(error: any) {
+    const url = this.router.url;
+    const errorMessage = error?.message ?? 'unknown';
+
+    this.analyticsService.trackEvent({
+      eventName: 'exception',
+      description: `Screen: ${url} | ${errorMessage}`,
+    });
+
+    console.error(GlobalErrorHandler.name, { error });
+  }
+}
+
+```
+
 ### `TestBed` rethrows errors by default
 
 In many cases, `ErrorHandler` may only log errors and otherwise allow the application to continue running. In tests, however, you almost always want to surface these errors. Angular's `TestBed` rethrows unexpected errors to ensure that errors caught by the framework cannot be unintentionally missed or ignored. In rare circumstances, a test may specifically attempt to ensure errors do not cause the application to be unresponsive or crash. In these situations, you can [configure `TestBed` to _not_ rethrow application errors](api/core/testing/TestModuleMetadata#rethrowApplicationErrors) with `TestBed.configureTestingModule({rethrowApplicationErrors: false})`.
diff --git a/packages/core/src/error_handler.ts b/packages/core/src/error_handler.ts
@@ -45,6 +45,9 @@ import {DestroyRef} from './linker/destroy_ref';
  * ```
  *
  * @publicApi
+ *
+ * @see [Unhandled errors in Angular](best-practices/error-handling)
+ *
  */
 export class ErrorHandler {
   /**
