Takumon/mean-blog

import { Pipe, PipeTransform } from '@angular/core';

@Pipe({ name: 'keys'})
export class KeysPipe implements PipeTransform {
  transform(value: any, args: string[]): any {
    const keys = [];
    for (const enumMember in value) {
      if (!isNaN(parseInt(enumMember, 10))) {
        keys.push(enumMember);
      }
    }

    return keys;
  }
}