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c# - Loading Nested Entities / Collections with Entity Framework

I am trying to Eagerly load all the related entities or collection of Entity in one call. My Entities Looks like:

Class Person
{
    public virtual long Id { get; set; }
    public virtual string FirstName { get; set; }
    public virtual string LastName { get; set; }
}

Class Employee
{
    public virtual long Id { get; set; }
    public DateTime AppointmentDate { get; set; }
    public virtual ICollection<EmployeeTitle> Titles { get; set; }
    public virtual Person Person { get; set; }
}

Class EmployeeTitle
{
    public virtual long Id { get; set; }
    public virtual bool IsCurrent { get; set; } 
    public virtual Title Title { get; set; }
}
Class Title
{
    public virtual long Id { get; set; }
    public virtual string Code { get; set; }
    public virtual string Description { get; set; }
}

What Iam trying to do is if i call a method to load all Employees, the result should include Person, List of EmployeeTitles including the code and description from Title I have been able to get to the third level i.e. getting the Employee with person and list of EmployeeTitle. I don't know how to get the title information with the EmployeeTitle. My code to get this is:

Context.Employees.Include("Person").Include(e => e.Titles).ToList();

Please shed some light on how to accomplish this. Thanks in advance.

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by (71.8m points)

You can try this:

Context.Employees
    .Include(e => e.Person)
    .Include(e => e.Titles.Select(t => t.Title))
    .ToList();

Select can be applied to a collection and loads navigation properties of the next level in the object graph.


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