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    <p>This is one of those problems that I wrestle with all the time. The most elegant approach that I've come up with (so far) is to simply create properties for the objects that handle all this for me. </p> <p>Ultimately it comes down to what situations you're using these classes in. For example in a gradebook application you'd drill-down through classes and into the student records. On the other hand, if you're doing a class registration application you'd have students that you add to classes, and drill down from the students into the classes they have registered to.</p> <p>Since we have no real scope of the application you're discussing, lets just roll generic style, shall we? Here's a class' classic Class class. (Ahh, that was fun.) The same ideas would apply to the Student class, however.</p> <pre><code>public class Class { IList&lt;Student&gt; _students; public IList&lt;Student&gt; Students { get { if(_students == null) { _students = new IList&lt;Student&gt;(); PopulateStudents(); // just for simplicity } } // no need for a setter usually... Use Students.Add(Student s) } } </code></pre> <p>What this allows you to do is on-demand loading of the students for this particular class. Supposing this is for web development, if your application is looking at information about a class, but doesn't need the list of students right now, why pull it from the database? <code>PopulateStudents()</code> can be as complex as you like. At minimum you'll put the database calls in there, but it wouldn't be a bad idea to throw some caching in there as well. </p> <p>If you do it properly, you won't really have to worry about what order you load the objects. They all get loaded when you want/need them, and require no thought on your part in your consumption code. When you call</p> <pre><code>Class c = new Class(id); // You do need a class to get its students... IList&lt;Students&gt; studentList = c.Students; </code></pre> <p>You don't really know if your data was already pulled, or still needs to be pulled, or what - and what do you care? Let the class itself handle the gritty details.</p> <p>Naturally there are considerations to make that you need to work out. For example, what about the 'new' Class (in other words, the class that isn't in the database <em>yet</em>). With some thorough programming, however, the end result is the same.</p>
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    1. COThanks for the thoughtful answer. This definitely seems like a great idea -- however, I'm a bit weary of putting of logic to populate the students from the data access layer inside the class itself. I think I will use this approach, though.
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