Angular pipes are a way to transform data in an Angular template. They are a simple way to show filtered or formatted data to the user. Angular comes with a set of built-in pipes, but you can also create your own custom pipes.
Built-in Pipes
Here are a few examples of built-in pipes:
Currency Pipe
The currency pipe formats a number as a currency string. It takes an optional parameter to specify the currency code, such as USD
for US dollars or EUR
for euros.
<p>{{ price | currency }}</p>
<p>{{ price | currency:'USD' }}</p>
<p>{{ price | currency:'EUR' }}</p>
Date Pipe
The date pipe formats a date object as a string. It takes an optional parameter to specify the format, such as short
, medium
, or long
.
<p>{{ date | date }}</p>
<p>{{ date | date:'short' }}</p>
<p>{{ date | date:'medium' }}</p>
<p>{{ date | date:'long' }}</p>
Uppercase Pipe
The uppercase pipe converts a string to uppercase.
<p>{{ name | uppercase }}</p>
Lowercase Pipe
The lowercase pipe converts a string to lowercase.
<p>{{ name | lowercase }}</p>
Custom Pipes
You can create your own custom pipes in Angular by implementing the Pipe
interface. Here is an example of a custom pipe that capitalizes the first letter of a string:
import { Pipe, PipeTransform } from '@angular/core';
@Pipe({
name: 'capitalize'
})
export class CapitalizePipe implements PipeTransform {
transform(value: string): string {
if (!value) return '';
return value.charAt(0).toUpperCase() + value.slice(1);
}
}
You can use the custom pipe in your templates just like the built-in pipes:
<p>{{ name | capitalize }}</p>
Conclusion
Angular pipes are a simple way to transform and format data in your templates. They can help you display data in a more user-friendly way, and you can even create your own custom pipes for specific needs.