Category: Angular

We often learn Angular presented with two options for working with forms: Template driven or reactive (or both!)

In several cases, small forms (for instance, a login screen, a single text input, or a single dropdown) don’t need that kind of verbosity.

In this post, we will look at five straightforward yet valuable features of the FormControl object used on its own without bringing any additional config to the table.

Source: 5 tips on using Angular FormControl | by Alain Chautard | Angular Training

This runs all spec files that are descendants of the “my-area” folder and in the “Edge” browser.

ng test --include "src/app/my-area/**/*.spec.ts" --browsers=Edge

run a single spec file:

ng test --include "src/app/myarea/**/mytest.component.spec.ts" --browsers=Edge

Angular v19 will make standalone: true the default for components, directives, and pipes.In v14 we introduced a developer preview “standalone” feature, which made it possible for the first time to build an application that didn’t rely on NgModules. Since then, standalone has been stabilized, and has become the recommended way to write Angular code by the Angular team. The CLI generates components with standalone: true by default, and the Angular docs teach standalone first to all new Angular developers. A

Source: The future is standalone!. Angular v19 will make standalone: true… | by Alex Rickabaugh | Sep, 2024 | Angular Blog

In this tutorial, we’re going to implement a polling mechanism using RxJs and Angular. Our goal is to retrieve and render information that gets refreshed periodically. Our example is going to be a currency service that displays up-to-date currency exchange rates

Source: How to do polling with RxJs and Angular? | by Alain Chautard | Angular Training

What if I need to read multiple properties from the object in that subscription?

Another way to put it is that you don’t want to end up doing something like this:

<p>First name: {{ (user$ | async)?.firstName }}</p>
<p>Last name: {{ (user$ | async)?.lastName }}</p>Code language: HTML, XML (xml)

The above code is pretty hard to read and requires one subscription for each property. This alone can be a disaster, as each subscription might trigger an HTTP request for the same data from the server!

Instead, you can do something like this, which uses only one subscription, stores the result in a local variable, then renders the data when it’s available. This technique works with any structural directive, such as *ngIf or *ngFor:

<div *ngIf="user$ | async as user">
   <p>First name: {{ user.firstName }}</p>
   <p>Last name: {{ user.lastName }}</p>
</div>

Source: Async pipe syntax tricks | Angular Newsletter