angular-docs-cn/modules/@angular/docs/core/03_pipes.md

Pipes

Pipes can be appended on the end of the expressions to translate the value to a different format. Typically used to control the stringification of numbers, dates, and other data, but can also be used for ordering, mapping, and reducing arrays. Pipes can be chained.

NOTE: Pipes are known as filters in Angular v1.

Pipes syntax is:

<div class="movie-copy">
  <p>
    {{ model.getValue('copy') | async | uppercase }}
  </p>
  <ul>
    <li>
      <b>Starring</b>: {{ model.getValue('starring') | async }}
    </li>
    <li>
      <b>Genres</b>: {{ model.getValue('genres') | async }}
    </li>
  <ul>
</div>