ServicePoint Класс
Определение
Важно!
Некоторые сведения относятся к предварительной версии продукта, в которую до выпуска могут быть внесены существенные изменения. Майкрософт не предоставляет никаких гарантий, явных или подразумеваемых, относительно приведенных здесь сведений.
Предоставляет управление подключениями для HTTP-подключений.
public ref class ServicePoint
public class ServicePoint
type ServicePoint = class
Public Class ServicePoint
- Наследование
-
ServicePoint
Примеры
В следующем примере кода создается объект ServicePoint, который подключается к www.contoso.com
URI.
// This example shows how to use the ServicePoint and ServicePointManager classes.
// The ServicePointManager class uses the ServicePoint class to manage connections
// to a remote host. The networking classes reuse service points for all
// requests to a given URI. In fact, the same ServicePoint object
// is used to issue requests to Internet resources identified by the same
// scheme identifier (for example, HTTP) and host fragment (for example, www.contoso.com).
// This should improve your application performance.
// Reusing service points in this way can help improve application performance.
#using <System.dll>
using namespace System;
using namespace System::Net;
using namespace System::Threading;
using namespace System::Text::RegularExpressions;
void ShowProperties( ServicePoint^ sp )
{
Console::WriteLine( "Done calling FindServicePoint()..." );
// Display the ServicePoint Internet resource address.
Console::WriteLine( "Address = {0}", sp->Address );
// Display the date and time that the ServicePoint was last
// connected to a host.
Console::WriteLine( "IdleSince = {0}", sp->IdleSince );
// Display the maximum length of time that the ServicePoint instance
// is allowed to maintain an idle connection to an Internet
// resource before it is recycled for use in another connection.
Console::WriteLine( "MaxIdleTime = {0}", sp->MaxIdleTime );
Console::WriteLine( "ConnectionName = {0}", sp->ConnectionName );
// Display the maximum number of connections allowed on this
// ServicePoint instance.
Console::WriteLine( "ConnectionLimit = {0}", sp->ConnectionLimit );
// Display the number of connections associated with this
// ServicePoint instance.
Console::WriteLine( "CurrentConnections = {0}", sp->CurrentConnections );
if ( sp->Certificate == nullptr )
Console::WriteLine( "Certificate = (null)" );
else
Console::WriteLine( "Certificate = {0}", sp->Certificate );
if ( sp->ClientCertificate == nullptr )
Console::WriteLine( "Client Certificate = (null)" );
else
Console::WriteLine( "Client Certificate = {0}", sp->ClientCertificate );
Console::WriteLine( "ProtocolVersion = {0}", sp->ProtocolVersion->ToString() );
Console::WriteLine( "SupportsPipelining = {0}", sp->SupportsPipelining );
Console::WriteLine( "UseNagleAlgorithm = {0} ", sp->UseNagleAlgorithm.ToString() );
Console::WriteLine( "Expect 100-continue = {0}", sp->Expect100Continue.ToString() );
}
void makeWebRequest( int hashCode, String^ Uri )
{
HttpWebResponse^ res = nullptr;
// Make sure that the idle time has elapsed, so that a new
// ServicePoint instance is created.
Console::WriteLine( "Sleeping for 2 sec." );
Thread::Sleep( 2000 );
try
{
// Create a request to the passed URI.
HttpWebRequest^ req = dynamic_cast<HttpWebRequest^>(WebRequest::Create( Uri ));
Console::WriteLine( "\nConnecting to {0} ............", Uri );
// Get the response object.
res = dynamic_cast<HttpWebResponse^>(req->GetResponse());
Console::WriteLine( "Connected.\n" );
ServicePoint^ currentServicePoint = req->ServicePoint;
// Display new service point properties.
int currentHashCode = currentServicePoint->GetHashCode();
Console::WriteLine( "New service point hashcode: {0}", currentHashCode );
Console::WriteLine( "New service point max idle time: {0}", currentServicePoint->MaxIdleTime );
Console::WriteLine( "New service point is idle since {0}", currentServicePoint->IdleSince );
// Check that a new ServicePoint instance has been created.
if ( hashCode == currentHashCode )
Console::WriteLine( "Service point reused." );
else
Console::WriteLine( "A new service point created." );
}
catch ( Exception^ e )
{
Console::WriteLine( "Source : {0}", e->Source );
Console::WriteLine( "Message : {0}", e->Message );
}
finally
{
if ( res != nullptr )
res->Close();
}
}
// Show the user how to use this program when wrong inputs are entered.
void showUsage()
{
Console::WriteLine( "Enter the proxy name as follows:" );
Console::WriteLine( "\tcs_servicepoint proxyName" );
}
int main()
{
array<String^>^args = Environment::GetCommandLineArgs();
int port = 80;
// Define a regular expression to parse the user's input.
// This is a security check. It allows only
// alphanumeric input strings between 2 to 40 characters long.
Regex^ rex = gcnew Regex( "^[a-zA-Z]\\w{1,39}$" );
if ( args->Length < 2 )
{
showUsage();
return -1;
}
String^ proxy = args[ 1 ];
if ( (!rex->Match(proxy))->Success)
{
Console::WriteLine( "Input string format not allowed." );
return -1;
}
String^ proxyAdd = String::Format( "http://{0}:{1}", proxy, port );
// Create a proxy object.
WebProxy^ DefaultProxy = gcnew WebProxy( proxyAdd,true );
// Set the proxy that all HttpWebRequest instances use.
WebRequest::DefaultWebProxy = DefaultProxy;
// Get the base interface for proxy access for the
// WebRequest-based classes.
IWebProxy^ Iproxy = WebRequest::DefaultWebProxy;
// Set the maximum number of ServicePoint instances to
// maintain. If a ServicePoint instance for that host already
// exists when your application requests a connection to
// an Internet resource, the ServicePointManager object
// returns this existing ServicePoint instance. If none exists
// for that host, it creates a new ServicePoint instance.
ServicePointManager::MaxServicePoints = 4;
// Set the maximum idle time of a ServicePoint instance to 10 seconds.
// After the idle time expires, the ServicePoint object is eligible for
// garbage collection and cannot be used by the ServicePointManager.
ServicePointManager::MaxServicePointIdleTime = 10000;
ServicePointManager::UseNagleAlgorithm = true;
ServicePointManager::Expect100Continue = true;
ServicePointManager::CheckCertificateRevocationList = true;
ServicePointManager::DefaultConnectionLimit = ServicePointManager::DefaultPersistentConnectionLimit;
// Create the Uri object for the resource you want to access.
Uri^ MS = gcnew Uri( "http://msdn.microsoft.com/" );
// Use the FindServicePoint method to find an existing
// ServicePoint object or to create a new one.
ServicePoint^ servicePoint = ServicePointManager::FindServicePoint( MS, Iproxy );
ShowProperties( servicePoint );
int hashCode = servicePoint->GetHashCode();
Console::WriteLine( "Service point hashcode: {0}", hashCode );
// Make a request with the same scheme identifier and host fragment
// used to create the previous ServicePoint object.
makeWebRequest( hashCode, "http://msdn.microsoft.com/library/" );
}
// This example shows how to use the ServicePoint and ServicePointManager classes.
// The ServicePointManager class uses the ServicePoint class to manage connections
// to a remote host. The networking classes reuse service points for all
// requests to a given URI. In fact, the same ServicePoint object
// is used to issue requests to Internet resources identified by the same
// scheme identifier (for example, HTTP) and host fragment (for example, www.contoso.com).
// This should improve your application performance.
// Reusing service points in this way can help improve application performance.
using System;
using System.Net;
using System.Threading;
using System.Text.RegularExpressions;
namespace Mssc.Services.ConnectionManagement
{
class TestServicePoint
{
private static void ShowProperties(ServicePoint sp)
{
Console.WriteLine("Done calling FindServicePoint()...");
// Display the ServicePoint Internet resource address.
Console.WriteLine("Address = {0} ", sp.Address.ToString());
// Display the date and time that the ServicePoint was last
// connected to a host.
Console.WriteLine("IdleSince = " + sp.IdleSince.ToString());
// Display the maximum length of time that the ServicePoint instance
// is allowed to maintain an idle connection to an Internet
// resource before it is recycled for use in another connection.
Console.WriteLine("MaxIdleTime = " + sp.MaxIdleTime);
Console.WriteLine("ConnectionName = " + sp.ConnectionName);
// Display the maximum number of connections allowed on this
// ServicePoint instance.
Console.WriteLine("ConnectionLimit = " + sp.ConnectionLimit);
// Display the number of connections associated with this
// ServicePoint instance.
Console.WriteLine("CurrentConnections = " + sp.CurrentConnections);
if (sp.Certificate == null)
Console.WriteLine("Certificate = (null)");
else
Console.WriteLine("Certificate = " + sp.Certificate.ToString());
if (sp.ClientCertificate == null)
Console.WriteLine("ClientCertificate = (null)");
else
Console. WriteLine("ClientCertificate = " + sp.ClientCertificate.ToString());
Console.WriteLine("ProtocolVersion = " + sp.ProtocolVersion.ToString());
Console.WriteLine("SupportsPipelining = " + sp.SupportsPipelining);
Console.WriteLine("UseNagleAlgorithm = " + sp.UseNagleAlgorithm.ToString());
Console.WriteLine("Expect 100-continue = " + sp.Expect100Continue.ToString());
}
private static void makeWebRequest(int hashCode, string Uri)
{
HttpWebResponse res = null;
// Make sure that the idle time has elapsed, so that a new
// ServicePoint instance is created.
Console.WriteLine("Sleeping for 2 sec.");
Thread.Sleep(2000);
try
{
// Create a request to the passed URI.
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(Uri);
Console.WriteLine("\nConnecting to " + Uri + " ............");
// Get the response object.
res = (HttpWebResponse)req.GetResponse();
Console.WriteLine("Connected.\n");
ServicePoint currentServicePoint = req.ServicePoint;
// Display new service point properties.
int currentHashCode = currentServicePoint.GetHashCode();
Console.WriteLine("New service point hashcode: " + currentHashCode);
Console.WriteLine("New service point max idle time: " + currentServicePoint.MaxIdleTime);
Console.WriteLine("New service point is idle since " + currentServicePoint.IdleSince );
// Check that a new ServicePoint instance has been created.
if (hashCode == currentHashCode)
Console.WriteLine("Service point reused.");
else
Console.WriteLine("A new service point created.") ;
}
catch (Exception e)
{
Console.WriteLine("Source : " + e.Source);
Console.WriteLine("Message : " + e.Message);
}
finally
{
if (res != null)
res.Close();
}
}
// Show the user how to use this program when wrong inputs are entered.
private static void showUsage()
{
Console.WriteLine("Enter the proxy name as follows:");
Console.WriteLine("\tcs_servicepoint proxyName");
}
public static void Main(string[] args)
{
int port = 80;
// Define a regular expression to parse the user's input.
// This is a security check. It allows only
// alphanumeric input strings between 2 to 40 characters long.
Regex rex = new Regex(@"^[a-zA-Z]\w{1,39}$");
if (args.Length < 1)
{
showUsage();
return;
}
string proxy = args[0];
if (!(rex.Match(proxy)).Success)
{
Console.WriteLine("Input string format not allowed.");
return;
}
string proxyAdd = "http://" + proxy + ":" + port;
// Create a proxy object.
WebProxy DefaultProxy = new WebProxy(proxyAdd, true);
// Set the proxy that all HttpWebRequest instances use.
WebRequest.DefaultWebProxy = DefaultProxy;
// Get the base interface for proxy access for the
// WebRequest-based classes.
IWebProxy Iproxy = WebRequest.DefaultWebProxy;
// Set the maximum number of ServicePoint instances to
// maintain. If a ServicePoint instance for that host already
// exists when your application requests a connection to
// an Internet resource, the ServicePointManager object
// returns this existing ServicePoint instance. If none exists
// for that host, it creates a new ServicePoint instance.
ServicePointManager.MaxServicePoints = 4;
// Set the maximum idle time of a ServicePoint instance to 10 seconds.
// After the idle time expires, the ServicePoint object is eligible for
// garbage collection and cannot be used by the ServicePointManager object.
ServicePointManager.MaxServicePointIdleTime = 10000;
ServicePointManager.UseNagleAlgorithm = true;
ServicePointManager.Expect100Continue = true;
ServicePointManager.CheckCertificateRevocationList = true;
ServicePointManager.DefaultConnectionLimit = ServicePointManager.DefaultPersistentConnectionLimit;
// Create the Uri object for the resource you want to access.
Uri MS = new Uri("http://msdn.microsoft.com/");
// Use the FindServicePoint method to find an existing
// ServicePoint object or to create a new one.
ServicePoint servicePoint = ServicePointManager.FindServicePoint(MS, Iproxy);
ShowProperties(servicePoint);
int hashCode = servicePoint.GetHashCode();
Console.WriteLine("Service point hashcode: " + hashCode);
// Make a request with the same scheme identifier and host fragment
// used to create the previous ServicePoint object.
makeWebRequest(hashCode, "http://msdn.microsoft.com/library/");
}
}
}
' This example shows how to use the ServicePoint and ServicePointManager classes.
' The ServicePointManager class uses the ServicePoint class to manage connections
' to a remote host. The networking classes reuse service points for all
' requests to a given URI. In fact, the same ServicePoint object
' is used to issue requests to Internet resources identified by the same
' scheme identifier (for example, HTTP) and host fragment (for example, www.contoso.com).
' Reusing service points in this way can help improve application performance.
Imports System.Net
Imports System.Threading
Imports System.Text.RegularExpressions
Namespace Mssc.Services.ConnectionManagement
Module M_TestServicePoint
Class TestServicePoint
Private Shared Sub ShowProperties(ByVal sp As ServicePoint)
Console.WriteLine("Done calling FindServicePoint")
' Display the ServicePoint Internet resource address.
Console.WriteLine(("Address = " + sp.Address.ToString()))
' Display the date and time that the ServicePoint was last
' connected to a host.
Console.WriteLine(("IdleSince = " + sp.IdleSince.ToString()))
' Display the maximum length of time that the ServicePoint instance
' is allowed to maintain an idle connection to an Internet
' resource before it is recycled for use in another connection.
Console.WriteLine(("MaxIdleTime = " + sp.MaxIdleTime.ToString()))
Console.WriteLine(("ConnectionName = " + sp.ConnectionName))
' Display the maximum number of connections allowed on this
' ServicePoint instance.
Console.WriteLine(("ConnectionLimit = " + sp.ConnectionLimit.ToString()))
' Display the number of connections associated with this
' ServicePoint instance.
Console.WriteLine(("CurrentConnections = " + sp.CurrentConnections.ToString()))
If sp.Certificate Is Nothing Then
Console.WriteLine("Certificate = (null)")
Else
Console.WriteLine(("Certificate = " + sp.Certificate.ToString()))
End If
If sp.ClientCertificate Is Nothing Then
Console.WriteLine("ClientCertificate = (null)")
Else
Console.WriteLine(("ClientCertificate = " + sp.ClientCertificate.ToString()))
End If
Console.WriteLine("ProtocolVersion = " + sp.ProtocolVersion.ToString())
Console.WriteLine(("SupportsPipelining = " + sp.SupportsPipelining.ToString()))
Console.WriteLine("UseNagleAlgorithm = " + sp.UseNagleAlgorithm.ToString())
Console.WriteLine("Expect 100-continue = " + sp.Expect100Continue.ToString())
End Sub
Private Shared Sub makeWebRequest(ByVal hashCode As Integer, ByVal Uri As String)
Dim res As HttpWebResponse = Nothing
' Make sure that the idle time has elapsed, so that a new
' ServicePoint instance is created.
Console.WriteLine("Sleeping for 2 sec.")
Thread.Sleep(2000)
Try
' Create a request to the passed URI.
Dim req As HttpWebRequest = CType(WebRequest.Create(Uri), HttpWebRequest)
Console.WriteLine((ControlChars.Lf + "Connecting to " + Uri + " ............"))
' Get the response object.
res = CType(req.GetResponse(), HttpWebResponse)
Console.WriteLine("Connected." + ControlChars.Lf)
Dim currentServicePoint As ServicePoint = req.ServicePoint
' Display new service point properties.
Dim currentHashCode As Integer = currentServicePoint.GetHashCode()
Console.WriteLine(("New service point hashcode: " + currentHashCode.ToString()))
Console.WriteLine(("New service point max idle time: " + currentServicePoint.MaxIdleTime.ToString()))
Console.WriteLine(("New service point is idle since " + currentServicePoint.IdleSince.ToString()))
' Check that a new ServicePoint instance has been created.
If hashCode = currentHashCode Then
Console.WriteLine("Service point reused.")
Else
Console.WriteLine("A new service point created.")
End If
Catch e As Exception
Console.WriteLine(("Source : " + e.Source))
Console.WriteLine(("Message : " + e.Message))
Finally
If Not (res Is Nothing) Then
res.Close()
End If
End Try
End Sub
' Show the user how to use this program when wrong inputs are entered.
Private Shared Sub showUsage()
Console.WriteLine("Enter the proxy name as follows:")
Console.WriteLine(ControlChars.Tab + "vb_servicepoint proxyName")
End Sub
' This is the program entry point. It allows the user to enter
' a server name that is used to locate its current homepage.
Public Shared Sub Main(ByVal args() As String)
Dim proxy As String = Nothing
Dim port As Integer = 80
' Define a regular expression to parse the user's input.
' This is a security check. It allows only
' alphanumeric input strings between 2 to 40 characters long.
Dim rex As New Regex("^[a-zA-Z]\w{1,39}$")
If args.Length = 0 Then
' Show how to use this program.
showUsage()
Return
End If
proxy = args(0)
If (Not (rex.Match(proxy)).Success) Then
Console.WriteLine("Input string format not allowed.")
Return
End If
' Create a proxy object.
Dim proxyAdd As String
proxyAdd = "http://" + proxy + ":" + port.ToString()
Dim DefaultProxy As New WebProxy(proxyAdd, True)
' Set the proxy that all HttpWebRequest instances use.
WebRequest.DefaultWebProxy = DefaultProxy
' Get the base interface for proxy access for the
' WebRequest-based classes.
Dim Iproxy As IWebProxy = WebRequest.DefaultWebProxy
' Set the maximum number of ServicePoint instances to maintain.
' Note that, if a ServicePoint instance for that host already
' exists when your application requests a connection to
' an Internet resource, the ServicePointManager object
' returns this existing ServicePoint. If none exists
' for that host, it creates a new ServicePoint instance.
ServicePointManager.MaxServicePoints = 4
' Set the maximum idle time of a ServicePoint instance to 10 seconds.
' After the idle time expires, the ServicePoint object is eligible for
' garbage collection and cannot be used by the ServicePointManager.
ServicePointManager.MaxServicePointIdleTime = 10000
ServicePointManager.UseNagleAlgorithm = True
ServicePointManager.Expect100Continue = True
ServicePointManager.CheckCertificateRevocationList = True
ServicePointManager.DefaultConnectionLimit = _
ServicePointManager.DefaultPersistentConnectionLimit
' Create the Uri object for the resource you want to access.
Dim MS As New Uri("http://msdn.microsoft.com/")
' Use the FindServicePoint method to find an existing
' ServicePoint object or to create a new one.
Dim servicePoint As ServicePoint = ServicePointManager.FindServicePoint(MS, Iproxy)
ShowProperties(servicePoint)
Dim hashCode As Integer = servicePoint.GetHashCode()
Console.WriteLine(("Service point hashcode: " + hashCode.ToString()))
' Make a request with the same scheme identifier and host fragment
' used to create the previous ServicePoint object.
makeWebRequest(hashCode, "http://msdn.microsoft.com/library/")
End Sub
End Class
End Module
End Namespace
Комментарии
Осторожность
WebRequest
, HttpWebRequest
, ServicePoint
и WebClient
устарели, и их не следует использовать для новой разработки. Вместо этого используйте HttpClient.
Класс ServicePoint обрабатывает подключения к интернет-ресурсу на основе сведений узла, передаваемых в универсальном коде ресурса ресурса (URI). Начальное подключение к ресурсу определяет сведения, которые поддерживает объект ServicePoint, который затем предоставляется всем последующим запросам этого ресурса.
ServicePoint объекты управляются классом ServicePointManager и создаются при необходимости методом ServicePointManager.FindServicePoint. ServicePoint объекты никогда не создаются напрямую, но всегда создаются и управляются классом ServicePointManager. Максимальное количество объектов ServicePoint, которые можно создать, устанавливается свойством ServicePointManager.MaxServicePoints.
Каждый объект ServicePoint поддерживает подключение к интернет-ресурсу до тех пор, пока он не будет неактивным, чем время, указанное в свойстве MaxIdleTime. Если ServicePoint превышает значение MaxIdleTime, его можно перезаработать в другое соединение. Значение по умолчанию MaxIdleTime задается свойством ServicePointManager.MaxServicePointIdleTime.
Если свойство ConnectionLeaseTimeout имеет значение, отличное от -1, и после истечения указанного времени, активное ServicePoint соединение закрывается после того, как он обслуживает следующий запрос. Это полезно для приложений, которые не требуют активных подключений, которые открываются неограниченное время, так как они по умолчанию.
Заметка
В условиях высокой нагрузки некоторые приложения могут выйти из свободных потоков в ThreadPool, что может привести к низкой производительности системы (например, высокой и переменной времени транзакций).
Свойства
Address |
Возвращает универсальный код ресурса (URI) сервера, к которому подключается этот объект ServicePoint. |
BindIPEndPointDelegate |
Указывает делегат для связывания локального IPEndPoint с ServicePoint. |
Certificate |
Возвращает сертификат, полученный для этого объекта ServicePoint. |
ClientCertificate |
Возвращает последний сертификат клиента, отправленный серверу. |
ConnectionLeaseTimeout |
Возвращает или задает количество миллисекунда, после которого закрывается активное ServicePoint подключение. |
ConnectionLimit |
Возвращает или задает максимальное количество подключений, разрешенных для этого объекта ServicePoint. |
ConnectionName |
Возвращает имя подключения. |
CurrentConnections |
Возвращает количество открытых подключений, связанных с этим объектом ServicePoint. |
Expect100Continue |
Возвращает или задает значение Boolean, определяющее, используется ли поведение 100-Continue. |
IdleSince |
Возвращает дату и время последнего подключения объекта ServicePoint к узлу. |
MaxIdleTime |
Возвращает или задает время, когда соединение, связанное с объектом ServicePoint, может оставаться бездействием до закрытия подключения. |
ProtocolVersion |
Возвращает версию протокола HTTP, используемого объектом ServicePoint. |
ReceiveBufferSize |
Возвращает или задает размер принимающего буфера для сокета, используемого этим ServicePoint. |
SupportsPipelining |
Указывает, поддерживает ли объект ServicePoint конвейерные подключения. |
UseNagleAlgorithm |
Возвращает или задает значение Boolean, определяющее, используется ли алгоритм Nagle для подключений, управляемых этим объектом ServicePoint. |
Методы
CloseConnectionGroup(String) |
Удаляет указанную группу подключений из этого объекта ServicePoint. |
Equals(Object) |
Определяет, равен ли указанный объект текущему объекту. (Унаследовано от Object) |
GetHashCode() |
Возвращает хэш-значение для экземпляра ServicePoint. |
GetHashCode() |
Служит хэш-функцией по умолчанию. (Унаследовано от Object) |
GetType() |
Возвращает Type текущего экземпляра. (Унаследовано от Object) |
MemberwiseClone() |
Создает неглубокую копию текущей Object. (Унаследовано от Object) |
SetTcpKeepAlive(Boolean, Int32, Int32) |
Включает или отключает параметр поддержания активности в TCP-подключении. |
ToString() |
Возвращает строку, представляющую текущий объект. (Унаследовано от Object) |