ObjectQuery.Include() => ObjectQuery.IncludeAll()

Question

下面的示例在查询客户时检索一组相关实体。在哪里可以找到递归遍历关系图并自动包含所有关系图的示例？

using(Entities context = new Entities())
{
    return context.Customers
        .Include("Address")
        .Include("Address.State")
        .Include("Address.State.Country")
        .Include("Phone")
        .Include("Phone.PhoneType").Single(c => c.LastName.StartsWith("Jo");
}

与

using(Entities context = new Entities())
{
    return context.Customers.IncludeAll().Single(c => c.LastName.StartsWith("Jo");
}

Answer 1

这样如何：

context.Customers.Include(c => c.Address.State.Country)
                 .Include(c => c.Phone.PhoneType)
                 .Single(c => c.LastName.StartsWith("Jo");

您不希望包含所有内容，因为并非在所有情况下，您都需要所有内容。