ObjectQuery<T>.Include(String) ObjectQuery<T>.Include(String) ObjectQuery<T>.Include(String) ObjectQuery<T>.Include(String) Method

Definition

Specifies the related objects to include in the query results.

public:
 System::Data::Objects::ObjectQuery<T> ^ Include(System::String ^ path);
public System.Data.Objects.ObjectQuery<T> Include (string path);
member this.Include : string -> System.Data.Objects.ObjectQuery<'T>
Public Function Include (path As String) As ObjectQuery(Of T)

Parameters

path
String String String String

Dot-separated list of related objects to return in the query results.

Returns

Exceptions

Examples

using (AdventureWorksEntities context =
    new AdventureWorksEntities())
{
    // Define an object query with a path that returns 
    // orders and items for a specific contact.
    Contact contact =
        context.Contacts.Include("SalesOrderHeaders.SalesOrderDetails")
        .FirstOrDefault();

    // Execute the query and display information for each item 
    // in the orders that belong to the first contact.
    foreach (SalesOrderHeader order in contact
        .SalesOrderHeaders)
    {
        Console.WriteLine(String.Format("PO Number: {0}",
            order.PurchaseOrderNumber));
        Console.WriteLine(String.Format("Order Date: {0}",
            order.OrderDate.ToString()));
        Console.WriteLine("Order items:");
        foreach (SalesOrderDetail item in order.SalesOrderDetails)
        {
            Console.WriteLine(String.Format("Product: {0} "
                + "Quantity: {1}", item.ProductID.ToString(),
                item.OrderQty.ToString()));
        }
    }
}
Using context As New AdventureWorksEntities()
    ' Define an object query with a path that returns 
    ' orders and items for a specific contact. 
    Dim contact As Contact = context.Contacts.Include("SalesOrderHeaders.SalesOrderDetails").FirstOrDefault()

    ' Execute the query and display information for each item 
    ' in the orders that belong to the first contact. 
    For Each order As SalesOrderHeader In contact.SalesOrderHeaders
        Console.WriteLine(String.Format("PO Number: {0}", order.PurchaseOrderNumber))
        Console.WriteLine(String.Format("Order Date: {0}", order.OrderDate.ToString()))
        Console.WriteLine("Order items:")
        For Each item As SalesOrderDetail In order.SalesOrderDetails
            Console.WriteLine(String.Format("Product: {0} Quantity: {1}", _
                                              item.ProductID.ToString(), item.OrderQty.ToString()))
        Next
    Next
End Using

Remarks

Query paths can be used with Entity SQL and LINQ queries.

Paths are all-inclusive. For example, if an include call indicates Include("Orders.OrderLines"), not only will OrderLines be included, but also Orders. For more information, see Loading Related Objects.

When you call the Include method, the query path is only valid on the returned instance of the ObjectQuery<T>. Other instances of ObjectQuery<T> and the object context itself are not affected.

Because the Include method returns the query object, you can call this method multiple times on an ObjectQuery<T> to specify multiple paths for the query, as in the following example:

// Create a SalesOrderHeader query with two query paths, 
// one that returns order items and a second that returns the 
// billing and shipping addresses for each order.
ObjectQuery<SalesOrderHeader> query =
    context.SalesOrderHeaders.Include("SalesOrderDetails").Include("Address");
' Create a SalesOrderHeader query with two query paths, 
' one that returns order items and a second that returns the 
' billing and shipping addresses for each order. 
Dim query As ObjectQuery(Of SalesOrderHeader) = context.SalesOrderHeaders.Include("SalesOrderDetails").Include("Address")

Applies to

See also