HttpWebRequest.Proxy 屬性

定義

命名空間:

System.Net

組件:

System.Net.Requests.dll

來源:

HttpWebRequest.cs

取得或設定要求的 Proxy 資訊。

public:
 virtual property System::Net::IWebProxy ^ Proxy { System::Net::IWebProxy ^ get(); void set(System::Net::IWebProxy ^ value); };

public override System.Net.IWebProxy? Proxy { get; set; }

member this.Proxy : System.Net.IWebProxy with get, set

Public Overrides Property Proxy As IWebProxy

屬性值

IWebProxy

用以代理 (proxy) 要求的 IWebProxy 物件。 呼叫 Select 屬性可以設定預設值。

例外狀況

ArgumentNullException

Proxy 設定為 null。

InvalidOperationException

要求已經藉由呼叫 GetRequestStream()、BeginGetRequestStream(AsyncCallback, Object)、GetResponse() 或 BeginGetResponse(AsyncCallback, Object) 啟動。

SecurityException

此呼叫者沒有要求的作業權限。

範例

下列程式代碼範例會 Proxy 使用 方法來取得要求的 Proxy 資訊。

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

// Obtain the 'Proxy' of the  Default browser.  
IWebProxy ^ proxy = myWebRequest->Proxy;
// Print the Proxy Url to the console.
if (proxy) 
{
    Console::WriteLine("Proxy: {0}",
        proxy->GetProxy(myWebRequest->RequestUri));
} 
else 
{
    Console::WriteLine("Proxy is null; no proxy will be used");
}

WebProxy ^ myProxy = gcnew WebProxy;

Console::WriteLine("\nPlease enter the new Proxy Address that is to be set:");
Console::WriteLine("(Example:http://myproxy.example.com:port)");
String ^ proxyAddress;

try 
{
    proxyAddress = Console::ReadLine();
    if (proxyAddress->Length > 0) {
        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 newUri object to 'myProxy' object so that new myProxy settings can be set.
        myProxy->Address = newUri;
        // Create a NetworkCredential object and associate it with the Proxy property of request object.
        myProxy->Credentials =
            gcnew NetworkCredential(username, password);
        myWebRequest->Proxy = myProxy;
    }
    Console::WriteLine("\nThe Address of the  new Proxy settings are {0}",
                  myProxy->Address);
    HttpWebResponse ^ myWebResponse =
        (HttpWebResponse ^) (myWebRequest->GetResponse());

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

// Obtain the 'Proxy' of the  Default browser.
IWebProxy proxy = myWebRequest.Proxy;
// Print the Proxy Url to the console.
if (proxy != null)
{
    Console.WriteLine("Proxy: {0}", proxy.GetProxy(myWebRequest.RequestUri));
}
else
{
    Console.WriteLine("Proxy is null; no proxy will be used");
}

WebProxy myProxy=new WebProxy();

Console.WriteLine("\nPlease enter the new Proxy Address that is to be set:");
Console.WriteLine("(Example:http://myproxy.example.com:port)");
string proxyAddress;

try
{
    proxyAddress =Console.ReadLine();
    if(proxyAddress.Length>0)
    {
        Console.WriteLine("\nPlease enter the Credentials (may not be needed)");
        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 newUri object to 'myProxy' object so that new myProxy settings can be set.
        myProxy.Address=newUri;
        // Create a NetworkCredential object and associate it with the
        // Proxy property of request object.
        myProxy.Credentials=new NetworkCredential(username,password);
        myWebRequest.Proxy=myProxy;
    }
    Console.WriteLine("\nThe Address of the  new Proxy settings are {0}",myProxy.Address);
    HttpWebResponse myWebResponse=(HttpWebResponse)myWebRequest.GetResponse();

' Create a new request to the mentioned URL.				
Dim myWebRequest As HttpWebRequest = CType(WebRequest.Create("http://www.microsoft.com"), HttpWebRequest)

      ' Obtain the 'Proxy' of the  Default browser.  
      Dim proxy as IWebProxy = CType(myWebRequest.Proxy, IWebProxy)
      ' Print the Proxy Url to the console.
If Not proxy Is Nothing Then
    Console.WriteLine("Proxy: {0}", proxy.GetProxy(myWebRequest.RequestUri))
Else
    Console.WriteLine("Proxy is null; no proxy will be used")
End If

Dim myProxy As New WebProxy()

Console.WriteLine(ControlChars.Cr + "Please enter the new Proxy Address that is to be set ")
Console.WriteLine("(Example:http://myproxy.example.com:port)")
Dim proxyAddress As String
Try
    proxyAddress = Console.ReadLine()
    If proxyAddress.Length = 0 Then
        myWebRequest.Proxy = myProxy
    Else
        Console.WriteLine(ControlChars.Cr + "Please enter the Credentials (may not be needed)")
        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 newUri object to 'myProxy' object so that new myProxy settings can be set.
        myProxy.Address = newUri
        ' Create a NetworkCredential object and associate it with the Proxy property of request 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 HttpWebResponse = CType(myWebRequest.GetResponse(), HttpWebResponse)

備註

Proxy 屬性會識別 WebProxy 物件，以用來處理向網際網路資源發出的要求。 若要指定不應使用 Proxy，請將 Proxy 屬性設定為 GlobalProxySelection.GetEmptyWebProxy 方法所傳回的 Proxy 執行個體。

本機電腦或應用程式組態檔可能會指定要使用的預設 Proxy。 Proxy如果指定 屬性，則 屬性中的 Proxy Proxy 設定會覆寫本機計算機或應用程式組態檔，而 HttpWebRequest 實例會使用指定的 Proxy 設定。 如果在組態檔中未指定任何 Proxy，而且 Proxy 未指定 屬性，則 HttpWebRequest 類別會使用繼承自本機電腦上的 Internet Explorer 的 Proxy 設定。 如果 Internet Explorer 中沒有 Proxy 設定，則會將要求直接傳送至伺服器。

類別會 HttpWebRequest 剖析 Proxy 略過清單，其通配符繼承自 Internet Explorer，與略過清單相同，由 Internet Explorer 直接剖析。 例如，類別 HttpWebRequest 會剖析 Internet Explorer 中 “nt*” 的略過清單，作為 “nt.*” 的正則表達式。 因此，“http://nt.com” 的 URL 會使用 HttpWebRequest 類別和使用 Internet Explorer 略過 Proxy。

HttpWebRequest 類別支援本機 Proxy 略過。 如果符合下列任何條件，該類別會將目的地視為本機：

• 目的地包含一般名稱 (URL 中沒有點)。

• 目的地包含回送位址 (Loopback 或 IPv6Loopback)，或目的地包含指派給本機電腦的 IPAddress。

• 目的地的網域尾碼符合本機電腦的網域尾碼 (DomainName)。

呼叫、 BeginGetRequestStream或方法，在要求啟動之後變更 Proxy 屬性會擲回 InvalidOperationException。 GetResponseGetRequestStreamBeginGetResponse 如需 proxy 元素的資訊，請參閱 <defaultProxy>元素 (網路設定) 。

另請參閱

• DefaultProxy 元素 (網路設定)
• 設定網際網路應用程式
• Proxy 組態
• 自動 Proxy 偵測