How to fetch data with EF one to many relationship

Question

How to fetch data with EF on one to many relationship.
ie if i have a table name Person(personID as primary key) and another table name streetLivedIn(personID as foreign key). Now i force my controller method to pass an object of type person

var persons=db.persons();
return View(persons);

Now i want to display Person details along with street(ie that what stored at streetLivedInTable) he/she lived at.
suppose i have an Entityset of person

public class Persons
{
   public string Name{get;set;}
   //NAVIGATIONL PROP. 
   public virtual ICollection<streetLivedIn>{get;set}
}

Answer 1

Suppose the navigational property name is Streets .

public class Persons
{
   public string Name { get; set; }
   //NAVIGATIONL PROP. 
   public virtual ICollection<streetLivedIn> Streets { get; set }
}

Then you can use the Include method to eager load this property.

var persons = db.persons.Include("Streets");
return View(persons);

You can display this in various ways. Eg

@foreach (var person in Model)
{
     <div>@person.Name</div>

         @foreach (var street in person.Streets)
         {
               <div>@street.Name</div>
         }
}

Or you can use the WebGrid , MvcContrib Grid , etc

Answer 2

Assuming you don't want to expose the Entity Framework data model directly to the view, and instead do a conversion to business objects you create, I would simply iterate the EF datamodel with a double foreach loop. Entity Framework creates the one-to-many-references for you using containment - why not take advantage of that.

I prefix the EF-generated classses with "Ef" for clarity.

var personList = new List<Person>();
foreach (var efPerson in EfPersons)
{
    var person = new Person
    { 
        Name = efPerson.Name,
        StreetsLivedIn = new List<StreetLivedIn>();
    }
    foreach (var efStreet in efPerson.EfStreetsLivedIn)
    {
        var street = new StreetLivedIn { Name = efStreet.Name; }
        person.StreetsLivedIn.Add(street);
    }
    personList.Add(person);
}
return View(personList);