Angular Interview Practice

What defines a custom pipe in Angular?

1. A pipe that transforms input data in a unique way

2. A pipe created by Angular developers only

3. A built-in pipe with modified functionality

4. A pipe that cannot accept parameters

The correct answer is: A pipe that transforms input data in a unique way

A custom pipe in Angular is defined primarily by its ability to transform input data in a unique way according to specific requirements. By creating a custom pipe, developers can implement tailored transformations that adjust the format, manipulate data, or apply specific logic beyond the capabilities of standard built-in pipes. For instance, a developer might create a custom pipe to format date strings into a specific format, convert numerical values into currency, or filter lists based on dynamic criteria. This characteristic of transforming input data is essential, as it emphasizes the flexibility and adaptability of custom pipes in addressing diverse application needs. While the other options present different aspects regarding pipes in Angular, they don't encapsulate the core definition of what a custom pipe signifies. Custom pipes are not limited to those developed solely by Angular developers, nor do they necessarily inherit or modify functionality from built-in pipes. Additionally, the ability to accept parameters is actually a common feature of many custom pipes to allow for more versatile transformations. Thus, the essence of a custom pipe rests on its unique transformation capabilities.