Angular 2 - ngFor index after a pipe

Question

In Angular 2 when using ngFor how would I get the original index for an object within an array after it has been passed through a pipe?

For example if I have an arra

Answer 1

You can also use reduce method to keep original index:

@Pipe({
  name: 'appFilter',
  pure: false
})
export class AppFilterPipe implements PipeTransform {
  transform(values: any[], arg1: any, arg2: any): any {
    return values.reduce((acc, value, index) => 
       value[arg1] === arg2 ? [...acc, { index, value }] : acc, []);
  }
}

and then in html

{{item.index}} - {{item.value.id}}

Plunker Example