Chapter 2: Understanding and Using Angular Directives

In this chapter, you'll learn about Angular directives in depth. You'll learn about attribute directives, with a really good real-world example of using a highlight directive. You'll also write your first structural directive and see how ViewContainer and TemplateRef services work together to add/remove elements from the Document Object Model (DOM), just as in the case of *ngIf, and you'll create some really cool attribute directives that do different tasks. Finally, you'll learn how to use multiple structural directives on the same HyperText Markup Language (HTML) element and how to enhance template type checking for your custom directives.

Here are the recipes we're going to cover in this chapter:

• Using attribute directives to handle the appearance of elements
• Creating a directive to calculate the read time for articles
• Creating a basic directive that allows you to vertically scroll to an element
• Writing your first custom structural directive
• How to use *ngIf and *ngSwitch together
• Enhancing template type checking for your custom directives