如何使用 LINQ 制作累積濾波器？

Question

這是我的方法，我只過濾一個，我需要它們是累積的

private IQueryable<PublicationModel> FilterByTreatmentStatus(IQueryable<PublicationModel> selectedData, int? filterTreatmentOption)
        {
            if (filterTreatmentOption.HasValue)
            {
                switch (filterTreatmentOption)
                {
                    case (int)PublicationTreatStatus.NotTreated:
                        return selectedData.Where(x => x.PublicationStatus == 0);
                    case (int)PublicationTreatStatus.Treated:
                        return selectedData.Where(x => x.PublicationStatus == 1);
                    case (int)PublicationTreatStatus.TreatedWithoutProvidence:
                        return selectedData.Where(x => x.PublicationStatus == 2);
                    default:
                        return selectedData;
                }
            }

            return selectedData;
        }

Answer 1

在這里你 go - 使用標志，所以你的枚舉可以保存多個值

[Flags]
public enum FilterTreatmentOption
{
    NotTreated = 1,
    Treated = 2,
    TreatedWithoutProvidence = 4
}


private IQueryable<PublicationModel> FilterByTreatmentStatus(IQueryable<PublicationModel> selectedData, FilterTreatmentOption filterTreatmentOption)
{
    if (filterTreatmentOption.HasFlag(PublicationTreatStatus.NotTreated))
        selectedData = selectedData.Where(x => x.PublicationStatus == 0);
    if (filterTreatmentOption.HasFlag(PublicationTreatStatus.Treated))
        selectedData = selectedData.Where(x => x.PublicationStatus == 1);
    if (filterTreatmentOption.HasFlag(PublicationTreatStatus.TreatedWithoutProvidence))
        selectedData = selectedData.Where(x => x.PublicationStatus == 2);
    return selectedData;
}