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copied!<p>Well, if I understand your question correctly, you can inspect the meta-model for a data context instance. The meta-model describes the tables, columns and associations in your model. Basically you want to look at associations on a table where the association is 1-to-many. </p> <p>This doesn't involve retrieving any data, as you are not actually working with entity instances, just the information that describes them.</p> <p>This code should do it:</p> <pre><code>public static string[] GetChildEntities<T>(DataContext context, T entity) { var mapping = context.Mapping.GetTable(typeof(T)); return mapping.RowType.Associations.Where(a => a.IsMany) .Select(a => a.ThisMember.Name).ToArray(); } </code></pre> <p>This will return the names of any properties that expose the <code>EntitySet</code> instances for the given parent entity.</p> <p><strong>EDIT</strong></p> <p>This code finds the first 1->* association between the parent and child entities based on the meta-model, retrieves the value of the EntitySet property on the parent entity, and adds the child entity to that set. This should work for most basic LINQ to SQL implementations.</p> <pre><code>public static void AddChild<P, C>(DataContext context, P parent, C child) where P : class where C : class { var parentMapping = context.Mapping.GetTable(typeof(P)); var childAssociation = parentMapping.RowType.Associations .Where(a => a.IsMany && a.OtherType.Type == typeof(C)) .FirstOrDefault(); if (childAssociation != null) { var entitySet = (EntitySet<C>) childAssociation.ThisMember .MemberAccessor .GetBoxedValue(parent); entitySet.Add(child); } }</code></pre>

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