多对多对另一对多对多对单个实体

问题描述：

对于使用实体框架的多对多关系，我有一个相当简单的问题。多对多对另一对多对多对单个实体

情况是这样的我有3种型号SectionName：

public class SectionName : BaseEntity 
{ 
    public SectionName() 
    { 
     SectionsSuffix = new List<SectionSuffix>(); 
    } 

    [Required] 
    public string Name { get; set; } 

    public ICollection<SectionSuffix> SectionsSuffix { get; set; } 
}

科后缀：

[Table("SectionsSuffix")] 
public class SectionSuffix : BaseEntity 
{ 
    public SectionSuffix() 
    { 
     SectionLines = new List<SectionLine>(); 
     SectionsName = new List<SectionName>(); 
    } 

    [Required] 
    public string Name { get; set; } 

    public ICollection<SectionLine> SectionLines { get; set; } 
    public ICollection<SectionName> SectionsName { get; set; } 
}

而且SectionLines：

[Table("SectionLines")] 
public class SectionLine : BaseEntity 
{ 
    public SectionLine() 
    { 
     SectionsSuffix = new List<SectionSuffix>(); 
    } 

    [Required] 
    public string Name { get; set; } 

    public ICollection<SectionSuffix> SectionsSuffix { get; set; } 
}

现在SectionsName是由许多与许多人SectionsSuffix和许多到SectionLines在上下文中使用FluentApi相关和接线表：

protected override void OnModelCreating(DbModelBuilder modelBuilder) 
    { 
     modelBuilder.Entity<SectionName>() 
      .HasMany(suffix => suffix.SectionsSuffix) 
      .WithMany(name => name.SectionsName) 
      .Map(nameSuffix => 
      { 
       nameSuffix.ToTable("SectionsNameSuffix"); 
       nameSuffix.MapLeftKey("SectionNameId"); 
       nameSuffix.MapRightKey("SectionSuffixId"); 
      }); 

     modelBuilder.Entity<SectionSuffix>() 
      .HasMany(line => line.SectionLines) 
      .WithMany(suffix => suffix.SectionsSuffix) 
      .Map(nameSuffix => 
      { 
       nameSuffix.ToTable("SectionsSuffixLines"); 
       nameSuffix.MapLeftKey("SectionSuffixId"); 
       nameSuffix.MapRightKey("SectionLinesId"); 
      }); 
    }

现在，如果有当我打电话SectionsNames没问题，我可以得到SectionsSuffix名单，我想这一个电话让还SectionNames名单猛吃具体SectionSuffix，这可能吗？

现在使用存储库模式的过程是这样的：

IList<SectionName> sections = SectionRepository.GetAll(x => x.SectionsSuffix).ToList(); 

    public virtual IEnumerable<T> GetAll(params Expression<Func<T, object>>[] includes) 
    { 
     IQueryable query = includes.Aggregate(_dbSet.AsQueryable(), (current, include) => current.Include(include)); 
     return (IEnumerable<T>) query; 
    }

答

回答是相当简单的，我会需要使用：

IList<SectionName> sections = SectionRepository.GetAll(name => name.SectionsSuffix, 
name => name.SectionsSuffix.Select(suffix => suffix.SectionLines)).ToList(); 

public virtual IEnumerable<T> GetAll(params Expression<Func<T, object>>[] includes) 
{ 
    IQueryable query = includes.Aggregate(_dbSet.AsQueryable(), (current, include) => current.Include(include)); 
    return (IEnumerable<T>) query; 
}

答

如果我想查询某事。像你想要做的那样，它会是这样的：

using System; 
using System.Data.Entity; 

public class SectionRepository 
{ 
    private readonly _context; 


    public SectionRepository(IMyDbContext context) 
    { 
     _context = context 
    } 

    public ICollection<SectionName> GetAll() 
    { 
     return _context.SectionNames 
      .Include(sn => sn.SectionsSuffix.SectionLine) 
      .Select(sn => sn).ToList(); 
    } 
}

请试试看，上面的代码没有经过测试。

多对多对另一对多对多对单个实体

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