
Angular Cookbook
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Form validations are pretty straightforward in Angular, the reason being the super-awesome validators that Angular provides out of the box. These validators are synchronous, meaning that as soon as you change the input, the validators kick in and provide you with information about the validity of the values right away. But sometimes, you might rely on some validations from a backend API, for instance. These situations would require something called asynchronous validators. In this recipe, you're going to create your first asynchronous validator.
The project that we are going to work with resides in chapter08/start_here/asynchronous-validator
inside the cloned repository:
npm install
to install the dependencies of the project. ng serve -o
.This should open the app in a new browser tab and you should see something like...