过滤相关实体或导航属性，其中实体框架 6 中有连接表

Question

I have three entities Role , RoleUser and User

I want to select each Compulsory Role and load the related User 's where the RoleUser.RecordID in the join table is equal to a given value.

Using the UOW and GenericReposiity Get(...) method I would call ...

.Get(role => role.Compulsory == true, null, "RoleUser.User") to select all the compulsory role's and load all User for the navigation RoleUser.User .

How can I filter them, is it possible using the implemented Get() method?

Entities

    public class Role
    {
        public int RoleID { get; set; }

        public bool Compulsory { get; set; }

        public virtual IList<RoleUser> RoleUser { get; set; }       
    }


    public class RoleUser
    {
        public string UserID { get; set; }

        public virtual User User { get; set; }


        public Guid RecordID { get; set; }

        public virtual Record Record { get; set; }


        public int RoleID { get; set; }

        public virtual Role Role { get; set; }
    }


    public class User
    {
        public string userID { get; set; }
    }

Get

    public virtual IList<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();
        }
    }

Answer 1

No , you cant filter the RoleUser from this Get method. if you want to filter RoleUser you want to project them into another list.

You can filter your Role based on the RoleUser table.

Include will always bring full data in the table unless you use IQuerable Projection.

var rolesWithAnyUserName = UnitOfWork.Role
                                     .Get(role => role.Compulsory == true && role.RoleUser
                                   .Any(g=>g.RoleUserName=="Name"), null, "RoleUser.User") 

This will only filter the Role based on the RoleUser filter

If you need to filter Include tables write the query where you can send IQuerable to the database

Try something like this , this will filter both Role and RoleUser

var result = DataContext.Role.Where(role => role.Compulsory == true )
                .Include(gl => gl.RoleUser)
                .Select(x => new
                {
                    role = x,
                    roleUsers= x.RoleUser.Where(g => g.Id == 1),
                }).ToList();