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WebRequest.Proxy Property

Definition

When overridden in a descendant class, gets or sets the network proxy to use to access this Internet resource.

public:
 virtual property System::Net::IWebProxy ^ Proxy { System::Net::IWebProxy ^ get(); void set(System::Net::IWebProxy ^ value); };
public virtual System.Net.IWebProxy Proxy { get; set; }
public virtual System.Net.IWebProxy? Proxy { get; set; }
member this.Proxy : System.Net.IWebProxy with get, set
Public Overridable Property Proxy As IWebProxy

Property Value

The IWebProxy to use to access the Internet resource.

Exceptions

Any attempt is made to get or set the property, when the property is not overridden in a descendant class.

Examples

The following example displays the current network proxy address and allows the user to assign a new network proxy address and port number.

// Create a new request to the mentioned URL.
WebRequest^ myWebRequest = WebRequest::Create( "http://www.contoso.com" );

WebProxy^ myProxy = gcnew WebProxy;
// Obtain the Proxy Prperty of the  Default browser.
myProxy = (WebProxy^)(myWebRequest->Proxy);

// Print myProxy address to the console.
Console::WriteLine( "\nThe actual default Proxy settings are {0}", myProxy->Address );
try
{
   Console::WriteLine( "\nPlease enter the new Proxy Address to be set " );
   Console::WriteLine( "The format of the address should be http://proxyUriAddress:portaddress" );
   Console::WriteLine( "Example:http://proxyadress.com:8080" );
   String^ proxyAddress;
   proxyAddress = Console::ReadLine();

   if ( proxyAddress->Length == 0 )
   {
      myWebRequest->Proxy = myProxy;
   }
   else
   {
      Console::WriteLine( "\nPlease enter the Credentials" );
      Console::WriteLine( "Username:" );
      String^ username;
      username = Console::ReadLine();
      Console::WriteLine( "\nPassword:" );
      String^ password;
      password = Console::ReadLine();
      
      // Create a new Uri object.
      Uri^ newUri = gcnew Uri( proxyAddress );
      
      // Associate the new Uri object to the myProxy object.
      myProxy->Address = newUri;
      
      // Create a NetworkCredential object and is assign to the Credentials
      // property of the Proxy object.
      myProxy->Credentials = gcnew NetworkCredential( username,password );
      myWebRequest->Proxy = myProxy;
   }
   Console::WriteLine( "\nThe Address of the  new Proxy settings are {0}", myProxy->Address );
   WebResponse^ myWebResponse = myWebRequest->GetResponse();
   
   // Print the  HTML contents of the page to the console.
   Stream^ streamResponse = myWebResponse->GetResponseStream();
   StreamReader^ streamRead = gcnew StreamReader( streamResponse );
   array<Char>^ readBuff = gcnew array<Char>(256);
   int count = streamRead->Read( readBuff, 0, 256 );
   Console::WriteLine( "\nThe contents of the Html pages are :" );
   while ( count > 0 )
   {
      String^ outputData = gcnew String( readBuff,0,count );
      Console::Write( outputData );
      count = streamRead->Read( readBuff, 0, 256 );
   }
   
   // Close the Stream object.
   streamResponse->Close();
   streamRead->Close();
   
   // Release the HttpWebResponse Resource.
   myWebResponse->Close();
   Console::WriteLine( "\nPress any key to continue........." );
   Console::Read();
}
catch ( UriFormatException^ e ) 
{
   Console::WriteLine( "\nUriFormatException is thrown->Message is {0}", e->Message );
   Console::WriteLine( "\nThe format of the myProxy address you entered is invalid" );
   Console::WriteLine( "\nPress any key to continue........." );
   Console::Read();
}
   // Create a new request to the mentioned URL.				
   WebRequest myWebRequest=WebRequest.Create("http://www.contoso.com");

   WebProxy myProxy=new WebProxy();
   // Obtain the Proxy Prperty of the  Default browser.  
   myProxy=(WebProxy)myWebRequest.Proxy;

   // Print myProxy address to the console.
   Console.WriteLine("\nThe actual default Proxy settings are {0}",myProxy.Address);
try
   {
       Console.WriteLine("\nPlease enter the new Proxy Address to be set ");
       Console.WriteLine("The format of the address should be http://proxyUriAddress:portaddress");
       Console.WriteLine("Example:http://proxyadress.com:8080");
       string proxyAddress;
       proxyAddress =Console.ReadLine();

       if(proxyAddress.Length==0)
       {
           myWebRequest.Proxy=myProxy;
       }
       else
       {
           Console.WriteLine("\nPlease enter the Credentials");
           Console.WriteLine("Username:");
           string username;
           username =Console.ReadLine();
           Console.WriteLine("\nPassword:");
           string password;
           password =Console.ReadLine();

           // Create a new Uri object.
           Uri newUri=new Uri(proxyAddress);

           // Associate the new Uri object to the myProxy object.
           myProxy.Address=newUri;

           // Create a NetworkCredential object and is assign to the Credentials property of the Proxy object.
           myProxy.Credentials=new NetworkCredential(username,password);
           myWebRequest.Proxy=myProxy;
       }
       Console.WriteLine("\nThe Address of the  new Proxy settings are {0}",myProxy.Address);
       WebResponse myWebResponse=myWebRequest.GetResponse();

       // Print the  HTML contents of the page to the console.
       Stream streamResponse=myWebResponse.GetResponseStream();
       StreamReader streamRead = new StreamReader( streamResponse );
       Char[] readBuff = new Char[256];
       int count = streamRead.Read( readBuff, 0, 256 );
       Console.WriteLine("\nThe contents of the Html pages are :");	
       while (count > 0) 
       {
           String outputData = new String(readBuff, 0, count);
           Console.Write(outputData);
           count = streamRead.Read(readBuff, 0, 256);
       }

       // Close the Stream object.
       streamResponse.Close();
       streamRead.Close();

       // Release the HttpWebResponse Resource.
       myWebResponse.Close();
       Console.WriteLine("\nPress any key to continue.........");
       Console.Read();				
   }
   catch(UriFormatException e)
   {
       Console.WriteLine("\nUriFormatException is thrown.Message is {0}",e.Message);
       Console.WriteLine("\nThe format of the myProxy address you entered is invalid");
       Console.WriteLine("\nPress any key to continue.........");
       Console.Read();
   }

  ' Create a new request to the mentioned URL.				
  Dim myWebRequest As WebRequest = WebRequest.Create("http://www.contoso.com")
  Dim myProxy As New WebProxy()

  ' Obtain the Proxy Prperty of the  Default browser. 
   myProxy = CType(myWebRequest.Proxy, WebProxy)

  ' Print myProxy address to the console.
  Console.WriteLine(ControlChars.Cr + "The actual default Proxy settings are {0}", myProxy.Address)

  Try
      Console.WriteLine(ControlChars.Cr + "Please enter the new Proxy Address to be set ")
      Console.WriteLine("The format of the address should be http://proxyUriAddress:portaddress")
      Console.WriteLine("Example:http://moon.proxy.com:8080")
      Dim proxyAddress As String
      proxyAddress = Console.ReadLine()

      If proxyAddress.Length = 0 Then
          myWebRequest.Proxy = myProxy
      Else
          Console.WriteLine(ControlChars.Cr + "Please enter the Credentials")
          Console.WriteLine("Username:")
          Dim username As String
          username = Console.ReadLine()
          Console.WriteLine(ControlChars.Cr + "Password:")
          Dim password As String
          password = Console.ReadLine()

         ' Create a new Uri object.
          Dim newUri As New Uri(proxyAddress)

          ' Associate the new Uri object to the myProxy object.
          myProxy.Address = newUri

          ' Create a NetworkCredential object and is assign to the Credentials property of the Proxy object.
          myProxy.Credentials = New NetworkCredential(username, password)
          myWebRequest.Proxy = myProxy
          
      End If
      Console.WriteLine(ControlChars.Cr + "The Address of the  new Proxy settings are {0}", myProxy.Address)
      Dim myWebResponse As WebResponse = myWebRequest.GetResponse()

      ' Print the  HTML contents of the page to the console.
      Dim streamResponse As Stream = myWebResponse.GetResponseStream()

      Dim streamRead As New StreamReader(streamResponse)
      Dim readBuff(256) As [Char]
      Dim count As Integer = streamRead.Read(readBuff, 0, 256)
      Console.WriteLine(ControlChars.Cr + "The contents of the Html pages are :")

      While count > 0
          Dim outputData As New [String](readBuff, 0, count)
          Console.Write(outputData)
          count = streamRead.Read(readBuff, 0, 256)

      End While

 ' Close the Stream object.
      streamResponse.Close()
streamRead.Close()

' Release the HttpWebResponse Resource.
  myWebResponse.Close()
      Console.WriteLine(ControlChars.Cr + "Press any key to continue.........")
      Console.Read()
  Catch e As UriFormatException
      Console.WriteLine(ControlChars.Cr + "{0}", e.Message)
      Console.WriteLine(ControlChars.Cr + "The format of the myProxy address you entered is invalid")
   End Try

Remarks

Caution

WebRequest, HttpWebRequest, ServicePoint, and WebClient are obsolete, and you shouldn't use them for new development. Use HttpClient instead.

The Proxy property identifies the network proxy that the request uses to access the Internet resource. The request is made through the proxy server rather than directly to the Internet resource.

Note

The WebRequest class is an abstract class. The actual behavior of WebRequest instances at run time is determined by the descendant class returned by the WebRequest.Create method. For more information about default values and exceptions, see the documentation for the descendant classes, such as HttpWebRequest and FileWebRequest.

Applies to

See also