AdjustSort() for "Angular CDK Table" article

snippet.adjust-sort.table.component.ts

adjustSort(key: string) {
  if (this.sortKey$.value === key) {
    if (this.sortDirection$.value === 'asc') {
      this.sortDirection$.next('desc');
    } else {
      this.sortDirection$.next('asc');
    }
    return;
  }

  this.sortKey$.next(key);
  this.sortDirection$.next('asc');
}