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Kafeel Ahmad (kaf shekh)
Kafeel Ahmad (kaf shekh)

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Angular Pipe

Angular pipes are a powerful feature in the Angular framework that allow you to transform data before displaying it in the template. Pipes are used to format, filter, and sort data in a concise and easy-to-read way.
Using a pipe in Angular is as simple as adding the pipe name to the expression in the template. For example, if you have a date object in your component and you want to display it in a specific format, you can use the built-in ‘date’ pipe:

<p>{{ currentDate | date:'dd/MM/yyyy' }}</p>
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In this example, the ‘date’ pipe formats the ‘currentDate’ property to the desired format of ‘dd/MM/yyyy’. The pipe takes the value on the left side of the pipe (in this case, ‘currentDate’) and transforms it according to the parameters on the right side of the pipe (in this case, the format string).
Pipes can also be chained together to perform multiple transformations on the same data. For example, you could use the ‘uppercase’ and ‘slice’ pipes to display only the first 3 characters of a string in uppercase:

<p>{{ 'hello world' | uppercase | slice:0:3 }}</p>

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In this example, the ‘uppercase’ pipe transforms the string to uppercase, and the ‘slice’ pipe takes the first 3 characters of the resulting string.
Angular also provides several built-in pipes for common use cases, such as ‘currency’, ‘decimal’, ‘percent’, and ‘async’. These pipes can be used to format numbers, percentages, and asynchronous data in a consistent and easy-to-read way.
In addition to the built-in pipes, Angular allows you to create custom pipes to perform more complex transformations on your data. Custom pipes are created as classes that implement the ‘PipeTransform’ interface, and can be added to your module’s ‘declarations’ array to make them available in your templates.

import { Pipe, PipeTransform } from '@angular/core';

@Pipe({ name: 'myCustomPipe' })
export class MyCustomPipe implements PipeTransform {
  transform(value: string, arg1: number, arg2: string): string {
    // perform transformation on value using arg1 and arg2
    return transformedValue;
  }
}
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In this example, the ‘MyCustomPipe’ class implements the ‘PipeTransform’ interface and defines a ‘transform’ method that takes a string value and two arguments. The ‘transform’ method performs some transformation on the value using the provided arguments and returns the transformed value.
Overall, pipes are a powerful tool in Angular that allow you to transform data in a consistent and easy-to-read way. Whether you’re formatting dates or transforming complex data structures, pipes can help you keep your templates clean and maintainable.

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