ObjectQuery<t>.Include(String) Method (System.Data.Objects)

Parameters

// 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()))
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")