ObjectContext.Connection Properti
Definisi
Penting
Beberapa informasi terkait produk prarilis yang dapat diubah secara signifikan sebelum dirilis. Microsoft tidak memberikan jaminan, tersirat maupun tersurat, sehubungan dengan informasi yang diberikan di sini.
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
Objek DbConnection yang merupakan koneksi.
Pengecualian
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.