SharePoint Framework ListView Command Set Extension - get selected items

ListViewCommandCommandSet.ts

@override
public onExecute(event: IListViewCommandSetExecuteEventParameters): void {
  switch (event.commandId) {
      case 'COMMAND_1':
          // Check if the user selected some items
          if (event.selectedRows.length > 0) {
              // Check the selected rows
              event.selectedRows.forEach((row: RowAccessor, index: number) => {
                  alert(`Field ID: ${row.getValueByName('ID')} - Field title: ${row.getValueByName('Title')}`);
              });
          }
          break;
      default:
          throw new Error('Unknown command');
  }
}