angular / 11.2.14 / api / common / slicepipe.html /

SlicePipe

pipe impure

Creates a new Array or String containing a subset (slice) of the elements.

{{ value_expression | slice : start [ : end ] }}

Exported from

Input value

value string | ReadonlyArray

Parameters

start number
end number

Optional. Default is undefined.

Usage notes

All behavior is based on the expected behavior of the JavaScript API Array.prototype.slice() and String.prototype.slice().

When operating on an Array, the returned Array is always a copy even when all the elements are being returned.

When operating on a blank value, the pipe returns the blank value.

List Example

This ngFor example:

@Component({
  selector: 'slice-list-pipe',
  template: `<ul>
    <li *ngFor="let i of collection | slice:1:3">{{i}}</li>
  </ul>`
})
export class SlicePipeListComponent {
  collection: string[] = ['a', 'b', 'c', 'd'];
}

produces the following:

<li>b</li>
<li>c</li>

String Examples

@Component({
  selector: 'slice-string-pipe',
  template: `<div>
    <p>{{str}}[0:4]: '{{str | slice:0:4}}' - output is expected to be 'abcd'</p>
    <p>{{str}}[4:0]: '{{str | slice:4:0}}' - output is expected to be ''</p>
    <p>{{str}}[-4]: '{{str | slice:-4}}' - output is expected to be 'ghij'</p>
    <p>{{str}}[-4:-2]: '{{str | slice:-4:-2}}' - output is expected to be 'gh'</p>
    <p>{{str}}[-100]: '{{str | slice:-100}}' - output is expected to be 'abcdefghij'</p>
    <p>{{str}}[100]: '{{str | slice:100}}' - output is expected to be ''</p>
  </div>`
})
export class SlicePipeStringComponent {
  str: string = 'abcdefghij';
}

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Licensed under the Creative Commons Attribution License 4.0.
https://v11.angular.io/api/common/SlicePipe