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POProblems when mapping a private property
 

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  1. POProblems when mapping a private property
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    <p>I have two entity classes Project and Product with one-to-many association:</p> <pre><code>public class Product { public string Id {get; set;} public virtual Project Project {get; set;} } public class Project { public string Id {get; set;} protected virtual List&lt;Product&gt; Products {get; set;} public ReadOnlyCollection&lt;Product&gt; GetProducts() { return Products.AsReadOnly(); } public class PropertyAccessExpressions { public static Expression&lt;Func&lt;Project, ICollection&lt;Product&gt;&gt;&gt; Products = x =&gt; x.Products; } } public class MyDbContext: DbContext { public MyDbContext(string connectionString): base(connectionString){} public DbSet&lt;Project&gt; Projects {get; set;} public DbSet&lt;Product&gt; Products {get; set;} protected override void OnModelCreating(DbModelBuilder modelBuilder) { //// project.GetProducts() fails for the following configuratin //modelBuilder.Entity&lt;Product&gt;() // .HasRequired(p =&gt; p.Project).WithMany(Project.PropertyAccessExpressions.Products); // The following is OK modelBuilder.Entity&lt;Project&gt;() .HasMany(Project.PropertyAccessExpressions.Products).WithRequired(p =&gt; p.Project); } } class Program { static void Main(string[] args) { var context = new MyDbContext(@"data source=localhost;initial catalog=MyTestDb;integrated security=True;"); context.Database.Delete(); context.Database.Create(); var project1 = new Project { Id = "ProjectId1" }; context.Projects.Add(project1); context.Products.Add(new Product { Id = "ProductId1", Project = project1 }); context.Products.Add(new Product { Id = "ProductId2", Project = project1 }); context.SaveChanges(); var project = context.Projects.ToList()[0];; var products = project.GetProducts().ToList(); Debug.Assert(products.Count == 2); } } </code></pre> <p>To map the protected property, I use <a href="http://blog.cincura.net/232731-mapping-private-protected-properties-in-entity-framework-4-x-code-first/" rel="nofollow">this solution</a>.</p> <p>But I encountered the following problems:</p> <p>1) if I configure the one-to-many association between Project and Product with </p> <pre><code>modelBuilder.Entity&lt;Product&gt;.HasRequied(p =&gt; p.Project).WithMany(Project.PropertyAccessExpressions.Products); </code></pre> <p>Then the Project.GetProducts() fails and it seems the lazy loading does not work. But if I change to</p> <pre><code>modelBuilder.Entity&lt;Project&gt; .HasMany(Project.PropertyAccessExpressions.Products).WithRequired(p =&gt; p.Project); </code></pre> <p>Then everything is OK.</p> <p>2) If I change the property "Project.Products" from protected to <strong>public</strong>, then both of the above ways are OK.</p> <p>What's wrong in this situation?</p>
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    1. USuser1012036
    1. USuser1012036
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      1. VTUpMod
    2. VO
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    3. VO
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    1. COYour code is full of errors. It does not compile.
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      1. USGert Arnold
    2. COSorry. I have pasted the whole code here. I hope it works now.
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      1. USuser1012036
 

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