Loading a class that contains other classes

Question

I have an some classes in C#, using a Database Context what would be the best way to load a class that in essence references/contains other classes?

Consider the following:

public class SomeClass
{
    [Key]
    [Column("id")]
    public int Id { get; set; }

    [ForeignKey("AnotherClass")]
    [Column("anotherClassId")]
    public int AnotherClassId { get; set; }

    [ForeignKey("SomeOtherClass")]
    [Column("someOtherClassId")]
    public int SomeOtherClassId { get; set; }

    [NotMapped]
    public AnotherClass AnotherClass { get; set; }

    [NotMapped]
    public SomeOtherClass SomeOtherClass { get; set; }
}

public class AnotherClass
{
    [Key]
    [Column("id")]
    public int Id { get; set; }

    [Column("name")]
    public string Name { get; set; }
}

public class SomeOtherClass
{
    [Key]
    [Column("id")]
    public int Id { get; set; }

    [Column("name")]
    public string Name { get; set; }
}

public async Task<SomeClass> GetSomeClass(int id)
{
    SomeClass someClass = null;
    using (var db = new Database.Context())
    {
        someClass = await db.SomeClass.AsNoTracking().FirstOrDefaultAsync(s => s.Id == id);
    }
    return someClass;
}

This is pretty much where I'd use a Join, and in any other language where I just use straight SQL that's what i would have done.

I could use additional queries afterwards, like so:

someClass = await db.SomeClass.AsNoTracking().FirstOrDefaultAsync(s => s.Id == id);
someClass.AnotherClass = await db.AnotherClass.AsNoTracking().FirstOrDefaultAsync(a => a.Id == someClass.AnotherClassId);
someClass.SomeOtherClass = await db.SomeOtherClass.AsNoTracking().FirstOrDefaultAsync(s => s.Id == someClass.SomeOtherClassId);

But I'm certain that's incorrect.

Answer 1

You need to use the include syntax see Link

    var abc = db.SomeOtherClass
    .Include(db=> db.AnotherClass)
    .ToList();