Angular Interview Practice

Can Angular pipes accept parameters?

1. No, they cannot accept parameters

2. Yes, but only in string format

3. Yes, by passing them directly after the pipe

4. Yes, by passing them after a colon

The correct answer is: Yes, by passing them after a colon

Angular pipes can indeed accept parameters, and they do so by passing them after a colon in the template. This allows you to customize the behavior of the pipe based on the values you provide. For example, if you have a date pipe and you want to specify a particular format, you would use it in the template like this: `{{ someDate | date: 'shortDate' }}`. Here, 'shortDate' is the parameter that alters how the date is displayed. While it’s true that pipes are capable of accepting parameters, the idea that they can only accept strings is not accurate. Pipes can accept various types of parameters, including numbers, objects, and more, depending on how the pipe is implemented. Also, parameters are not passed directly without the colon; they are always prefixed by this symbol to distinguish them from the pipe itself in the syntax. Therefore, the correct understanding of passing parameters with a colon is fundamental to using Angular pipes effectively.