AngularJS Services
Angular services are singleton objects that carry out some sort of task. We also use AngularJS services to organize and share code across the application.Angular Services follow Single Responsibility Principle (SRP) and are wired together using dependency injection (DI). The Single Responsibility principle ensures that each object will have only a single responsibility. AngularJS includes services for different purposes. For example, $http service can be used to send an AJAX request to the remote server. AngularJS also allows you to create custom service for your application.
There are 5 different ways to create services in Angular:
1. Value
2. Factory
3. Service
4. Provider
5. Constant
Form Validation
An Angular form is a regular HTML form with few additional features. For each field (input, radio, select, etc.) in the form, we need an object of the FormControl class. The FormControl object gives information about that field. Its value, if the value is valid, and if it is not valid what are the validation errors, etc.
It also provides the state of the field such as touched, untouched, dirty, pristine, etc.
Similarly, a FormGroup is the collection of the FormControl objects. Every Angular form has at least one FormGroup. You may decide to have multiple FormGroups in use-cases like separating the handling of personal details and professional details sections of a user registration form.
All the properties of a FormGroup (valid, error, etc.) is also available to the FormControl. For instance, the valid property of a FormControl will return true if all FormControl instances are valid.
Example:
ng-submit
Enables binding AngularJS expressions to onsubmit events.
Additionally it prevents the default action (which for form means sending the request to the server and reloading the current page), but only if the form does not contain action, data-action, or x-action attributes.
More topics covered:
- ref types in service
- service inside service
- $ prefix only for angular services
- $http.post instead of submit
Links:
dotnethacker.home.blog 