ServicePoint Classe
Definizione
Importante
Alcune informazioni sono relative alla release non definitiva del prodotto, che potrebbe subire modifiche significative prima della release definitiva. Microsoft non riconosce alcuna garanzia, espressa o implicita, in merito alle informazioni qui fornite.
Fornisce la gestione delle connessioni per le connessioni HTTP.
public ref class ServicePoint
public class ServicePoint
type ServicePoint = class
Public Class ServicePoint
- Ereditarietà
-
ServicePoint
Esempio
Nell'esempio di codice seguente viene creato un oggetto ServicePoint che si connette all'URI www.contoso.com
.
// 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 != true )
{
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 != true)
{
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
Commenti
Cautela
WebRequest
, HttpWebRequest
, ServicePoint
e WebClient
sono obsoleti e non è consigliabile usarli per nuovi sviluppi. Usare invece HttpClient.
La classe ServicePoint gestisce le connessioni a una risorsa Internet in base alle informazioni sull'host passate nell'URI (Uniform Resource Identifier) della risorsa. La connessione iniziale alla risorsa determina le informazioni che l'oggetto ServicePoint gestisce, che viene quindi condiviso da tutte le richieste successive a tale risorsa.
ServicePoint oggetti vengono gestiti dalla classe ServicePointManager e vengono creati, se necessario, dal metodo ServicePointManager.FindServicePoint. ServicePoint oggetti non vengono mai creati direttamente, ma vengono sempre creati e gestiti dalla classe ServicePointManager. Il numero massimo di oggetti ServicePoint che è possibile creare viene impostato dalla proprietà ServicePointManager.MaxServicePoints.
Ogni oggetto ServicePoint mantiene la connessione a una risorsa Internet finché non è più inattiva rispetto all'ora specificata nella proprietà MaxIdleTime. Quando un ServicePoint supera il valore MaxIdleTime, può essere riciclato in un'altra connessione. Il valore predefinito di MaxIdleTime viene impostato dalla proprietà ServicePointManager.MaxServicePointIdleTime.
Quando la proprietà ConnectionLeaseTimeout è impostata su un valore diverso da -1 e dopo il tempo specificato, una connessione ServicePoint attiva viene chiusa dopo la successiva richiesta. Ciò è utile per le applicazioni che non richiedono connessioni attive aperte per un periodo illimitato, perché sono per impostazione predefinita.
Nota
In condizioni di carico elevato, alcune applicazioni possono esaurire thread liberi in ThreadPool, che possono causare prestazioni di sistema scarse ,ad esempio tempi di transazione elevati e variabili.
Proprietà
Address |
Ottiene l'URI (Uniform Resource Identifier) del server a cui si connette questo oggetto ServicePoint. |
BindIPEndPointDelegate |
Specifica il delegato per associare un IPEndPoint locale a un ServicePoint. |
Certificate |
Ottiene il certificato ricevuto per questo oggetto ServicePoint. |
ClientCertificate |
Ottiene l'ultimo certificato client inviato al server. |
ConnectionLeaseTimeout |
Ottiene o imposta il numero di millisecondi dopo il quale viene chiusa una connessione ServicePoint attiva. |
ConnectionLimit |
Ottiene o imposta il numero massimo di connessioni consentite in questo oggetto ServicePoint. |
ConnectionName |
Ottiene il nome della connessione. |
CurrentConnections |
Ottiene il numero di connessioni aperte associate all'oggetto ServicePoint. |
Expect100Continue |
Ottiene o imposta un valore Boolean che determina se viene utilizzato il comportamento 100-Continue. |
IdleSince |
Ottiene la data e l'ora dell'ultima connessione dell'oggetto ServicePoint a un host. |
MaxIdleTime |
Ottiene o imposta la quantità di tempo per cui una connessione associata all'oggetto ServicePoint può rimanere inattiva prima della chiusura della connessione. |
ProtocolVersion |
Ottiene la versione del protocollo HTTP utilizzato dall'oggetto ServicePoint. |
ReceiveBufferSize |
Ottiene o imposta le dimensioni del buffer ricevente per il socket utilizzato da questo ServicePoint. |
SupportsPipelining |
Indica se l'oggetto ServicePoint supporta le connessioni pipeline. |
UseNagleAlgorithm |
Ottiene o imposta un valore Boolean che determina se l'algoritmo Nagle viene utilizzato nelle connessioni gestite da questo oggetto ServicePoint. |
Metodi
CloseConnectionGroup(String) |
Rimuove il gruppo di connessioni specificato da questo oggetto ServicePoint. |
Equals(Object) |
Determina se l'oggetto specificato è uguale all'oggetto corrente. (Ereditato da Object) |
GetHashCode() |
Restituisce un valore hash per un'istanza di ServicePoint. |
GetHashCode() |
Funge da funzione hash predefinita. (Ereditato da Object) |
GetType() |
Ottiene il Type dell'istanza corrente. (Ereditato da Object) |
MemberwiseClone() |
Crea una copia superficiale del Objectcorrente. (Ereditato da Object) |
SetTcpKeepAlive(Boolean, Int32, Int32) |
Abilita o disabilita l'opzione keep-alive in una connessione TCP. |
ToString() |
Restituisce una stringa che rappresenta l'oggetto corrente. (Ereditato da Object) |