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The context is set up for lazy loading and seems that everything is working properly but:

public void Test_Lazy_Loading() {
    using (var context = new MyDbContext()) {
        var student = context.Students.First();
        var loaded = context.Entry(student).Collection(e => e.Classes).IsLoaded; // returns true
        Assert.IsFalse(loaded); // fails
    }
}

Does this test mean that CLasses is eager loaded? What is the best way to test that lazy loading is working?

roozbeh S
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  • As a side note: be careful when using the `using` statements with lazy loading. Because after your `using` statement, you cannot load the related entity lazily because the db is disposed and so the Eager Loading would be a better choice here. Reading this answer also could be helpful https://stackoverflow.com/a/34628138/2946329 – Salah Akbari Nov 18 '18 at 10:29
  • No, it indicates that `Classes` is loaded. But I don't see how `context.Students.First()` could do that. On the face of it eager loading (or lazy loading) shouldn't happen here. Maybe you triggered lazy loading in the debugger. – Gert Arnold Nov 18 '18 at 11:23
  • @GertArnold Sorry "students" was a typo I meant "classes". I mean since lazy loading is enabled,the `virtual IList Classes` should not be loaded since I haven't accessed it yet. Am I wrong? – roozbeh S Nov 18 '18 at 12:23
  • That's correct. And it shouldn't have been loaded by eager loading either. So to me it's unclear how the collection can be marked as loaded at that point if the code runs without debugging. If anything it must be lazy loading because eager loading always happens by explicitly calling `Include`. Maybe something in the `MyDbContext` class or the `Student` class. – Gert Arnold Nov 18 '18 at 12:30
  • You mean maybe there is a property or method in Student class that invokes loading? something like `public int numClasses { get { return Classes.Count;}}`? – roozbeh S Nov 18 '18 at 14:09

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