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entity framework - Conditional eager loading?

I want to load an entity and it's children conditionally (I only want to eager load the children when the child.IsActive == true). How do I perform the following?

var parent = 
    from p in db.tblParents.Include("tblChildren") <-- where tblChildren.IsActive == true
    where p.PrimaryKey == 1
    select p;

NOTE: I do not want to return an anonymous type.

Thanks.

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One way for doing so is:

var parent = from p in db.tblParents where p.PrimaryKey == 1
             select new {
                 Parent = p,
                 Children = p.tblChildren.Where(c => c.IsActive == true)
             }.ToList();


However, you might not like the idea to return an anonymous type, then I would suggest to code it this way:

var parent = (from p in db.tblParents where p.PrimaryKey == 1).Single();
var childrens = ctx.Contacts.Where(c => c.ParentID == 1 && c.IsActive == true);
foreach (var child in childrens) {
   parent.tblChildren.Add(child);
}

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