ObjectContext.Connection Properti

Definisi

Ruang nama:

System.Data.Objects

Rakitan:

System.Data.Entity.dll

Mendapatkan koneksi yang digunakan oleh konteks objek.

public:
 property System::Data::Common::DbConnection ^ Connection { System::Data::Common::DbConnection ^ get(); };

public System.Data.Common.DbConnection Connection { get; }

member this.Connection : System.Data.Common.DbConnection

Public ReadOnly Property Connection As DbConnection

Nilai Properti

DbConnection

Objek DbConnection yang merupakan koneksi.

Pengecualian

ObjectDisposedException

ObjectContext Ketika instans telah dibuang.

Contoh

Contoh ini membuat EntityConnection objek yang diteruskan ke konstruktor dari jangka panjang ObjectContext. Koneksi dibuka secara manual. EntityConnection Objek dan ObjectContext objek dibuang secara manual.

// Define the order ID for the order we want.
int orderId = 43680;

// Create an EntityConnection.
EntityConnection conn =
    new EntityConnection("name=AdventureWorksEntities");

// Create a long-running context with the connection.
AdventureWorksEntities context =
    new AdventureWorksEntities(conn);

try
{
    // Explicitly open the connection.
    if (conn.State != ConnectionState.Open)
    {
        conn.Open();
    }

    // Execute a query to return an order.
    SalesOrderHeader order =
        context.SalesOrderHeaders.Where(
        "it.SalesOrderID = @orderId", new ObjectParameter("orderId", orderId))
        .Execute(MergeOption.AppendOnly).First();

    // Change the status of the order.
    order.Status = 1;

    // You do not have to call the Load method to load the details for the order,
    // because  lazy loading is set to true
    // by the constructor of the AdventureWorksEntities object.
    // With  lazy loading set to true the related objects are loaded when
    // you access the navigation property. In this case SalesOrderDetails.

    // Delete the first item in the order.
    context.DeleteObject(order.SalesOrderDetails.First());

    // Save changes.
    if (0 < context.SaveChanges())
    {
        Console.WriteLine("Changes saved.");
    }

    // Create a new SalesOrderDetail object.
    // You can use the static CreateObjectName method (the Entity Framework
    // adds this method to the generated entity types) instead of the new operator:
    // SalesOrderDetail.CreateSalesOrderDetail(1, 0, 2, 750, 1, (decimal)2171.2942, 0, 0,
    //                                         Guid.NewGuid(), DateTime.Today));
    SalesOrderDetail detail = new SalesOrderDetail
    {
        SalesOrderID = 1,
        SalesOrderDetailID = 0,
        OrderQty = 2,
        ProductID = 750,
        SpecialOfferID = 1,
        UnitPrice = (decimal)2171.2942,
        UnitPriceDiscount = 0,
        LineTotal = 0,
        rowguid = Guid.NewGuid(),
        ModifiedDate = DateTime.Now
    };

    order.SalesOrderDetails.Add(detail);

    // Save changes again.
    if (0 < context.SaveChanges())
    {
        Console.WriteLine("Changes saved.");
    }
}
catch (InvalidOperationException ex)
{
    Console.WriteLine(ex.ToString());
}
finally
{
    // Explicitly dispose of the context and the connection.
    context.Dispose();
    conn.Dispose();
}

Keterangan

Properti ini mengembalikan objek koneksi yang diteruskan ke konstruktor atau dibuat selama konstruksi. Kepemilikan koneksi ditentukan oleh konstruktor yang digunakan.

Lihat juga

• Bekerja dengan Objek (Kerangka Kerja Entitas)