Question

我有一个相当复杂的数据模型，有30多个表。我正在使用Web API向Angular 2前端提供数据，并发现下载一个＆＃34;整个＆＃34;最容易。考虑到这并不涉及很多数据，所以它的所有子类都在一个项目中。

然而，我现在正在看下面的怪物：

var query = context.GlobalBcf
    .Include(x => x.Location)
    .Include(x => x.RadioEquipment.Model)
    .Include(x => x.RadioEquipment.RadioEquipmentSuppliers).ThenInclude(x => x.Supplier)
    .Include(x => x.RadioEquipment.RadioEquipmentTypes).ThenInclude(x => x.Type)
    .Include(x => x.GlobalBcfPowerSupplies).ThenInclude(x => x.PowerSupply)
    .Include(x => x.GlobalBcfApplications).ThenInclude(x => x.Application)
    .Include(x => x.OvtpType)
    .Include(x => x.BatteryType)
    .Include(x => x.AmountBattery)
    .Include(x => x.Bcfs)
    .Include(x => x.Bcfs).ThenInclude(x => x.Mode)
    .Include(x => x.Bcfs).ThenInclude(x => x.TrxSigBw1)
    .Include(x => x.Bcfs).ThenInclude(x => x.TrxSigBw2)
    .Include(x => x.Bcfs).ThenInclude(x => x.TrxSigBw3)
    .Include(x => x.Bcfs).ThenInclude(x => x.TrxSigBw4)
    .Include(x => x.Bcfs).ThenInclude(x => x.BcfSegments).ThenInclude(x => x.Segment).ThenInclude(x => x.Btses)
    .Include(x => x.Bcfs).ThenInclude(x => x.BcfSegments).ThenInclude(x => x.Segment.ExternalComponent)
    .Include(x => x.Bcfs).ThenInclude(x => x.BcfSegments).ThenInclude(x => x.Segment.Repeaters).ThenInclude(x => x.Type)
    .Include(x => x.Bcfs).ThenInclude(x => x.BcfSegments).ThenInclude(x => x.Segment.Repeaters).ThenInclude(x => x.FrequenceRepeaters).ThenInclude(x => x.Model)
    .Include(x => x.Bcfs).ThenInclude(x => x.BcfSegments).ThenInclude(x => x.Segment.Repeaters).ThenInclude(x => x.FrequenceRepeaters).ThenInclude(x => x.Supplier)
    .Include(x => x.Bcfs).ThenInclude(x => x.BcfSegments).ThenInclude(x => x.Segment.Repeaters).ThenInclude(x => x.MasterUnits).ThenInclude(x => x.Model)
    .Include(x => x.Bcfs).ThenInclude(x => x.BcfSegments).ThenInclude(x => x.Segment.Repeaters).ThenInclude(x => x.MasterUnits).ThenInclude(x => x.PowerSupply)
    .Include(x => x.Bcfs).ThenInclude(x => x.BcfSegments).ThenInclude(x => x.Segment.Repeaters).ThenInclude(x => x.MasterUnits).ThenInclude(x => x.Supplier)
    .Include(x => x.Bcfs).ThenInclude(x => x.BcfSegments).ThenInclude(x => x.Segment.Repeaters).ThenInclude(x => x.MasterUnits).ThenInclude(x => x.OpticRepeaters).ThenInclude(x => x.OtrxModel)
    .Include(x => x.Bcfs).ThenInclude(x => x.BcfSegments).ThenInclude(x => x.Segment.Repeaters).ThenInclude(x => x.MasterUnits).ThenInclude(x => x.OpticRepeaters).ThenInclude(x => x.RuModel)
    .Include(x => x.Bcfs).ThenInclude(x => x.BcfSegments).ThenInclude(x => x.Segment.Repeaters).ThenInclude(x => x.MasterUnits).ThenInclude(x => x.OpticRepeaters).ThenInclude(x => x.RuPowerSupply)
    .Include(x => x.Bcfs).ThenInclude(x => x.BcfSegments).ThenInclude(x => x.Segment.Repeaters).ThenInclude(x => x.MasterUnits).ThenInclude(x => x.OpticRepeaters).ThenInclude(x => x.RuMode)
    .AsQueryable();

return query.Single(x => x.Id == message.Id);

这显然很难维护，所以我想知道是否有可能将其拆分成更小，更易于维护的部分，而不是一遍又一遍地重复这些部分：

.Include(x => x.Bcfs)
.Include(x => x.Bcfs).ThenInclude(x => x.BcfSegments)
.Include(x => x.Bcfs).ThenInclude(x => x.BcfSegments).ThenInclude(x => x.Segment.Repeaters)
.Include(x => x.Bcfs).ThenInclude(x => x.BcfSegments).ThenInclude(x => x.Segment.Repeaters).ThenInclude(x => x.MasterUnits)
.Include(x => x.Bcfs).ThenInclude(x => x.BcfSegments).ThenInclude(x => x.Segment.Repeaters).ThenInclude(x => x.MasterUnits).ThenInclude(x => x.OpticRepeaters)。

任何提示，指示，想法？

Answer 1

我找到了一个解决方案，只需将代码片段分成不同的扩展名：

class SupraBigZone {
    public List<Zone> Zones {get; set;}
}

class Zone {
    public SupraBigZone SupraBigZone {get; set;}
    public List<SmallZone> SmallZones {get; set;}
}

class SmallZone {
    public Zone Zone {get; set;}
}

然后你有一个包含SupraBigZone的课程：

class Game {
    public SupraBigZone GameZone {get; set;}

    public OtherProperty OtherProperty {get; set;}
}

public static class IQueryableExtensions
{
    public static IIncludableQueryable<T, Zone> IncludeSupraBigZone<T>(this IQueryable<T> values, Func<T,SupraBigZone> getSupraBigZone) where T : class
    {
        return values
            .Include(c => getSupraBigZone(c)).ThenInclude(h => h.Zones).ThenInclude(z => z.SupraBigZone)
            .Include(c => getSupraBigZone(c)).ThenInclude(h => h.Zones).ThenInclude(z => z.SmallZones).ThenInclude(s => s.Zone);
    }
}

请注意，扩展名将Zone作为第二个泛型类型，这是因为在此示例中，最后一个包含区域。

在您的DbContext中，您可以按如下方式使用它：

public DbSet<Game> Games { get; set; }

public IQueryable<Car> GameWithDependencies
{
    get
    {
        return
            Games
            .IncludeSupraBigZone(g => g.GameZone)
            .Include(g => g.OtherProperty);
    }
}

拆分过长的IIncludableQueryable＆lt;＆gt;

1 个答案: