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POHow Model n--n relationship in EF Code First to automatically generated views work correctly?
 

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  1. POHow Model n--n relationship in EF Code First to automatically generated views work correctly?
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    <p>I use EF Code First and have a problem in n-n relationship, assume we have a singer that sing in some genres, so we need this models: Artist, Genre, and ArtistsGenres, I define Models as following:</p> <p>This is My Artist Model:</p> <pre><code>public class Artist { public long Id { get; set; } public string Name { get; set; } public ICollection&lt;Genre&gt; Genres { get; set; } } </code></pre> <p>And My Genre Model:</p> <pre><code>public class Genre { public long Id { get; set; } public string Title { get; set; } public ICollection&lt;Artist&gt; Artists { get; set; } } </code></pre> <p>And my context class:</p> <pre><code>public class MusicDB : DbContex { public DbSet&lt;Artist&gt; Artists { get; set; } public DbSet&lt;Genre&gt; Genres { get; set; } public DbSet&lt;ArtistsGenres&gt; ArtistsGenres { get; set; } protected override void OnModelCreating(DbModelBuilder modelBuilder) { modelBuilder.Entity&lt;Artist&gt;() .HasMany(a =&gt; a.Genres) .WithMany(g =&gt; g.Artists) .Map(model =&gt; { model.ToTable("ArtistsGenres"); model.MapLeftKey("Artist_Id"); model.MapRightKey("Genre_Id"); }); base.OnModelCreating(modelBuilder); } } </code></pre> <p>But there is not any relationship between Artists and Genres when MVC generate views automatically.</p> <p>For example, I need to change Genres of an Artist in edit view, in Create view I can set Genres for an Artist, or in Index View I want show genres for each Artist. But there isn't any generation for Genres in relation to Artist when MVC generate views automatically. </p> <p>I know I can access both Genres and Artists from both side but I am interesting in MVC automatically generate views as we want: for ex: for each artist show related Genres.</p> <p>How can I do this? Is my model correct? Is this true for any (n to n) relation that needs ICollection on both side? Or do I need some elements in overriding of <code>OnModelCreating</code> method in context class, for example something like this:</p> <pre><code>modelBuilder.Entity&lt;Artist&gt;() .HasMany(a =&gt; a.Genres) .WithMany(g =&gt; g.Artists); </code></pre> <p>Please help me, I don't know the exact implementation of NtoN relationship.</p>
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