EF發送包含列表到存儲庫通過參數

Question

我在這個時候我有存儲庫充滿了多個獲取方法。

E.q. Get1() => cxt.Entites.Include(e => e.obj1); Get2() => cxt.Entities.Include(e => e.obj1).Include(e => e.obj2)

依此類推。

有沒有好的方法，模式有一個GET方法，我可以通過參數發送inclues？

Answer 1

public virtual IEnumerable<TEntity> Get(
     Expression<Func<TEntity, bool>> filter = null, 
     Func<IQueryable<TEntity>, IOrderedQueryable<TEntity>> orderBy = null, 
     string includeProperties = "") 
    { 
     IQueryable<TEntity> query = dbSet; 

     if (filter != null) 
     { 
      query = query.Where(filter); 
     } 

     foreach (var includeProperty in includeProperties.Split 
      (new char[] { ',' }, StringSplitOptions.RemoveEmptyEntries)) 
     { 
      query = query.Include(includeProperty); 
     } 

     if (orderBy != null) 
     { 
      return orderBy(query).ToList(); 
     } 
     else 
     { 
      return query.ToList(); 
     } 
    } 

見msdn 庫模式您可以使用

_sampleRepostiory.Get(h=>h.Id>1,null,"Employees.Departments"); 

包括同與拉姆達

public virtual IEnumerable<TEntity> Get(
      Expression<Func<TEntity, bool>> filter = null, 
      Func<IQueryable<TEntity>, IOrderedQueryable<TEntity>> orderBy = null, 
      Expression<Func<TEntity, object>>[] includes) 
     { 
      IQueryable<TEntity> query = dbSet; 

      if (filter != null) 
      { 
       query = query.Where(filter); 
      } 

      if (includes != null) 
      { 
       query = includes.Aggregate(query, 
        (current, include) => current.Include(include)); 
      } 

      if (orderBy != null) 
      { 
       return orderBy(query).ToList(); 
      } 
      else 
      { 
       return query.ToList(); 
      } 
     } 

消耗它這樣

var query = context.Customers 
       .Get(x=>x.Id>1,null, 
        c => c.Address, 
        c => c.Orders.Select(o => o.OrderItems)); 

Similar SO question

Answer 2

我確實在我的項目如下：

public Entity[] GetAll(bool includeObj1, bool includeAllOthers) { 
    IQueryable<Entity> entity = ctx.Entities; 

    if (includeObj1) 
     entity = entity.Include(e => e.obj1); 

    if (includeAllOthers) { 
     entity = entity 
      .Include(e => e.obj2) 
      .Include(e => e.obj3) 
      .Include(e => e.obj4) 
      .Include(e => e.obj5); 
    } 

    return entity.ToArray(); 
} 

像includeObj1和includeObj2提供了論據從實現中分離出庫的消費者和封裝任何數據訪問邏輯。
直接傳遞「包含這些屬性」命令到存儲庫意味着您知道存儲庫的工作方式，並假定它是某種排除抽象的ORM。