Dhananjay Kumar

In Angular, content projection is used to project content in a component. Let’s take a closer look at how it works:

Content projection allows you to insert a shadow DOM in your component. To put it simply, if you want to insert HTML elements or other components in a component, then you do that using concept of content projection. In Angular, you achieve content projection using < ng-content >< /ng-content >.  You can make reusable components and scalable application by right use of content projection.

To understand content projection, let us consider GreetComponent as shown in the code listing below:

Now if you use GreetComponent in another component, and want to pass a greeting message from the parent component, then you should use the @Input() decorator. This way, a modified GreetComponnet will look like the listing below:

Using the @Input() decorator, you can pass a simple string to the GreetComponnet, but what if you need to pass different types of data to the GreetComponent such as:

1. Inner HTML
2. HTML Elements
3. Styled HTML
4. Another Component etc.

To pass or project styled HTML or another component, content projection is used. Let us modify the GreetComponent to use content projection in this code:

We are using to project content in the GreetComponent. When you use the GreetComponent, you’ll pass content as shown below:

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