c# 将 linq 数据库记录转换为类实例

Question

我不确定这是否是正确的处理方法，看起来很冗长，我想检查这是否是将 linq 结果转换为类的好方法：

 /// <summary>
/// A job header
/// </summary>
public class JobHeader
{
    public int ID { get; set; }
    public int? UserID { get; set; }
    public int? ClientID { get; set; }
    public string JobName { get; set; }
    public string Code { get; set; }
    public DateTime? DateAdded { get; set; }
    public int? StatusID { get; set; }
    public bool UniversalQuantity { get; set; }
    public bool UniversalDelivery { get; set; }
    public bool UniversalDeliveryDates { get; set; }
    public bool BuyerHidden { get; set; }
    public bool FullfillmentDone { get; set; }
    public string TNTCode { get; set; }
    public int? ContactUserID { get; set; }
    public string ContactDepartment { get; set; }
    public string ConactName { get; set; }
    public DateTime? DateSubmitted { get; set; }
    public bool CampaignJob { get; set; }
    public bool UniversalBusinessUnits { get; set; }
    public bool TenderJob { get; set; }
    public Jobs.JobLine[] JobLines { get; set; }

    /// <summary>
    /// Create instance on db record ID
    /// </summary>
    public JobHeader(int? RecordID)
    {
        if (RecordID != null)
        {
            using (MainContext db = new MainContext())
            {
                var q = (from h in db.tblJobHeaders where h.id == RecordID select h).SingleOrDefault();
                if (q != null)
                    LoadByRec(q);
            }
        }
    }
    public JobHeader(tblJobHeader Rec)
    {
        LoadByRec(Rec);
    }

    /// <summary>
    /// Sets properties to match database record
    /// </summary>
    private void LoadByRec(tblJobHeader Rec)
    {
        this.ID = Rec.id;
        this.UserID = Rec.userID;
        this.ClientID = Rec.ClientID;
        this.JobName = Rec.JobName;
        this.Code = Rec.JobCode;
        this.DateAdded = Rec.dateAdded;
        this.StatusID = Rec.statusID;
        this.UniversalQuantity = Rec.uniQty == 1;
        this.UniversalDelivery = Rec.uniDelivery == 1;
        this.UniversalDeliveryDates = Rec.uniDeliveryDates == 1;
        this.BuyerHidden = Rec.buyerHidden == 1;
        this.FullfillmentDone = Rec.fulfilmentDone == 1;
        this.TNTCode = Rec.jobTntCode;
        this.ContactUserID = Rec.JobClientContactID;
        this.ContactDepartment = Rec.JobClient;
        this.ConactName = Rec.JobAccountHandler;
        this.DateSubmitted = Rec.dateSubmitted;
        this.CampaignJob = Rec.isCampaignJob == 1;
        this.UniversalBusinessUnits = Rec.uniBusUnits == 1;
        this.TenderJob = Rec.isTenderJob == 1;
    }
}

首先我知道数据源是格式不正确（请忽略不正确的类型等），目前我对此无能为力。我的查询特别是关于这是从 Linq 结果创建类实例的最佳方法吗？它变得非常冗长，有很多属性。

Answer 1

你的方法是完全有效的，虽然有点手动。我参与过许多使用这种方法从数据库查询创建 C# 对象的项目。然而，有一些技术可用于从查询生成类型：

• 类型化数据集 - 一种稍微过时的方法
• Linq to SQL
• 实体框架

以上所有内容都可用于根据数据库模式生成类型。