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copied!<p>Not exactly your way, because I'm using POCO with state flags, but it can be applied to generated entities as well. This is a recursive approach to manage the state of the parent entity and children entities. This is the state manager class for the <code>Parent</code> entity:</p> <pre><code>public partial class ParentStateManager : IStateManager<Parent, MyObjContext> { private IStateManager<Child, MyObjContext> _ChildStateManager = new ChildStateManager(); public void ChangeState(Parent m, MyObjContext ctx) { if (m == null) return; ctx.Parents.Attach(m); if (m.IsDeleted) { ctx.ObjectStateManager.ChangeObjectState(m, System.Data.EntityState.Deleted); } else { if (m.IsNew) { ctx.ObjectStateManager.ChangeObjectState(m, System.Data.EntityState.Added); } else { if (m.IsDirty) { ctx.ObjectStateManager.ChangeObjectState(m, System.Data.EntityState.Modified); } } } SetRelationsState(m, ctx); } private void SetRelationsState(Parent m, MyObjContext ctx) { foreach (Child varChild in m.Children.Where(p => !p.IsDeleted)) { _ChildStateManager.ChangeState(varChild, ctx); } while (m.Children.Where(p => p.IsDeleted).Any()) { _ChildStateManager.ChangeState(m.Children.Where(p => p.IsDeleted).LastOrDefault(), ctx); } } } </code></pre> <p>And this is the state manager for the <code>Child</code> entity:</p> <pre><code>public partial class ChildStateManager : IStateManager<Child, MyObjContext> { public void ChangeState(Child m, MyObjContext ctx) { if (m == null) return; ctx.Children.Attach(m); if (m.IsDeleted) { ctx.ObjectStateManager.ChangeObjectState(m, System.Data.EntityState.Deleted); } else { if (m.IsNew) { ctx.ObjectStateManager.ChangeObjectState(m, System.Data.EntityState.Added); } else { if (m.IsDirty) { ctx.ObjectStateManager.ChangeObjectState(m, System.Data.EntityState.Modified); } } } SetRelationsState(m, ctx); } private void SetRelationsState(Child m, MyObjContext ctx) { } } </code></pre> <p><code>IStateManager</code> is a simple interface which only has <code>ChangeState</code> method. If the <code>Child</code> entity had a <code>GrandChild</code> collection, the <code>ChildStateManager.SetRelationsState()</code> method would call the <code>GrandChildStateManager.ChangeState()</code> and so on. It's a bit complicated, but it works for me and I generate the state manager code using T4 templates. </p>

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