WebHeaderCollection.IsRestricted 方法

定義

測試是否可設定指定的 HTTP 標頭。Tests whether the specified HTTP header can be set.

多載

IsRestricted(String)

測試是否可為要求設定指定的 HTTP 標頭。Tests whether the specified HTTP header can be set for the request.

IsRestricted(String, Boolean)

測試是否可以設定要求或回應之指定的 HTTP 標頭。Tests whether the specified HTTP header can be set for the request or the response.

IsRestricted(String)

測試是否可為要求設定指定的 HTTP 標頭。Tests whether the specified HTTP header can be set for the request.

public:
 static bool IsRestricted(System::String ^ headerName);
public static bool IsRestricted (string headerName);
static member IsRestricted : string -> bool
Public Shared Function IsRestricted (headerName As String) As Boolean

參數

headerName
String

要測試的標頭。The header to test.

傳回

如果標頭是受限制的,則為 true,否則為 falsetrue if the header is restricted; otherwise false.

例外狀況

headerNamenullEmptyheaderName is null or Empty.

headerName 包含無效的字元。headerName contains invalid characters.

範例

下列範例會檢查IsRestricted屬性,以查看是否禁止設定任何標頭。The following example checks the IsRestricted property to see if any headers are prohibited from being set.

try
{
   // Create a web request for S"www.msn.com".
   HttpWebRequest^ myHttpWebRequest = dynamic_cast<HttpWebRequest^>(WebRequest::Create( "http://www.msn.com" ));

   // Get the associated response for the above request.
   HttpWebResponse^ myHttpWebResponse = dynamic_cast<HttpWebResponse^>(myHttpWebRequest->GetResponse());

   // Get the headers associated with the response.
   WebHeaderCollection^ myWebHeaderCollection = myHttpWebResponse->Headers;
   for ( int i = 0; i < myWebHeaderCollection->Count; i++ )
   {
      // Check if the first response header is restriced.
      if ( WebHeaderCollection::IsRestricted( dynamic_cast<String^>(myWebHeaderCollection->AllKeys[ i ]) ) )
               Console::WriteLine( "' {0}' is a restricted header", myWebHeaderCollection->AllKeys[ i ] );
      else
               Console::WriteLine( "' {0}' is not a restricted header", myWebHeaderCollection->AllKeys[ i ] );
   }
   myHttpWebResponse->Close();
}
catch ( WebException^ e ) 
{
   Console::WriteLine( "\nWebException is thrown.\nMessage is: {0}", e->Message );
   if ( e->Status == WebExceptionStatus::ProtocolError )
   {
      Console::WriteLine( "Status Code : {0}", (dynamic_cast<HttpWebResponse^>(e->Response))->StatusCode );
      Console::WriteLine( "Status Description : {0}", (dynamic_cast<HttpWebResponse^>(e->Response))->StatusDescription );
      Console::WriteLine( "Server : {0}", (dynamic_cast<HttpWebResponse^>(e->Response))->Server );
   }
}
catch ( Exception^ e ) 
{
   Console::WriteLine( "Exception is thrown. Message is : {0}", e->Message );
}
    try {
        // Create a web request for "www.msn.com".
        HttpWebRequest myHttpWebRequest = (HttpWebRequest) WebRequest.Create("http://www.msn.com");

        // Get the associated response for the above request.
        HttpWebResponse myHttpWebResponse = (HttpWebResponse) myHttpWebRequest.GetResponse();

        // Get the headers associated with the response.
        WebHeaderCollection myWebHeaderCollection = myHttpWebResponse.Headers;
        
        for (int i = 0; i < myWebHeaderCollection.Count;i++)	
        {
        // Check if the first response header is restricted.
        if(WebHeaderCollection.IsRestricted(myWebHeaderCollection.AllKeys[i]))
            Console.WriteLine("'{0}' is a restricted header", myWebHeaderCollection.AllKeys[i]);
        else
            Console.WriteLine("'{0}' is not a restricted header", myWebHeaderCollection.AllKeys[i]);
        }
        myHttpWebResponse.Close();
    }
    catch(WebException e) {
        Console.WriteLine("\nWebException is thrown.\nMessage is:" + e.Message);
        if(e.Status == WebExceptionStatus.ProtocolError) {
            Console.WriteLine("Status Code : {0}", ((HttpWebResponse)e.Response).StatusCode);
            Console.WriteLine("Status Description : {0}", ((HttpWebResponse)e.Response).StatusDescription);
            Console.WriteLine("Server : {0}", ((HttpWebResponse)e.Response).Server);
        }
    }
    catch(Exception e) {
        Console.WriteLine("Exception is thrown. Message is :" + e.Message);
    }

}
Public Shared Sub Main()
Try
        'Create a web request for "www.msn.com".
        Dim myHttpWebRequest As HttpWebRequest = CType(WebRequest.Create("http://www.msn.com"), HttpWebRequest)
        
        'Get the associated response for the above request.
        Dim myHttpWebResponse As HttpWebResponse = CType(myHttpWebRequest.GetResponse(), HttpWebResponse)
        
        'Get the headers associated with the response.
        Dim myWebHeaderCollection As WebHeaderCollection = myHttpWebResponse.Headers
        
        'Check if the first response header is restricted.
    dim i as integer
    for i =0 to myWebHeaderCollection.Count-1
            If WebHeaderCollection.IsRestricted(myWebHeaderCollection.AllKeys(i)) Then
                Console.WriteLine("'{0}' is a restricted header", myWebHeaderCollection.AllKeys(i))
            Else
                Console.WriteLine("'{0}' is not a restricted header", myWebHeaderCollection.AllKeys(i))
            End If 
    next
    myHttpWebResponse.Close()
    Catch e As WebException
        Console.WriteLine(e.Message)
        If e.Status = WebExceptionStatus.ProtocolError Then
            Console.WriteLine("Status Code : {0}", CType(e.Response, HttpWebResponse).StatusCode)
            Console.WriteLine("Status Description : {0}", CType(e.Response, HttpWebResponse).StatusDescription)
            Console.WriteLine("Server : {0}", CType(e.Response, HttpWebResponse).Server)
        End If
    Catch e As Exception
        Console.WriteLine(e.Message)
    End Try
End Sub

備註

方法會傳回,表示標頭受到限制,而且必須使用屬性來設定,而不是直接或由系統設定。 true IsRestrictedThe IsRestricted method returns true to indicate that a header is restricted and must be set using properties instead of directly or is set by the system. 限制的標頭為:The restricted headers are:

  • 接受Accept

  • 連線Connection

  • Content-LengthContent-Length

  • Content-TypeContent-Type

  • 日期Date

  • 有望Expect

  • 主機Host

  • 如果-已修改-自起If-Modified-Since

  • RangeRange

  • 推薦者Referer

  • 傳輸-編碼Transfer-Encoding

  • 使用者代理程式User-Agent

  • Proxy-連線Proxy-Connection

IsRestricted(String, Boolean)

測試是否可以設定要求或回應之指定的 HTTP 標頭。Tests whether the specified HTTP header can be set for the request or the response.

public:
 static bool IsRestricted(System::String ^ headerName, bool response);
public static bool IsRestricted (string headerName, bool response);
static member IsRestricted : string * bool -> bool
Public Shared Function IsRestricted (headerName As String, response As Boolean) As Boolean

參數

headerName
String

要測試的標頭。The header to test.

response
Boolean

Framework 測試回應或要求嗎?Does the Framework test the response or the request?

傳回

如果標頭是受限制的,則為 true,否則為 falsetrue if the header is restricted; otherwise, false.

例外狀況

headerNamenullEmptyheaderName is null or Empty.

headerName 包含無效的字元。headerName contains invalid characters.

範例

下列範例會檢查IsRestricted屬性,以查看是否禁止設定任何要求標頭。The following example checks the IsRestricted property to see if any request headers are prohibited from being set.

try
{
   // Create a web request for S"www.msn.com".
   HttpWebRequest^ myHttpWebRequest = dynamic_cast<HttpWebRequest^>(WebRequest::Create( "http://www.msn.com" ));

   // Get the associated response for the above request.
   HttpWebResponse^ myHttpWebResponse = dynamic_cast<HttpWebResponse^>(myHttpWebRequest->GetResponse());

   // Get the headers associated with the response.
   WebHeaderCollection^ myWebHeaderCollection = myHttpWebResponse->Headers;
   for ( int i = 0; i < myWebHeaderCollection->Count; i++ )
   {
      // Check if the first response header is restriced.
      if ( WebHeaderCollection::IsRestricted( dynamic_cast<String^>(myWebHeaderCollection->AllKeys[ i ]) ) )
               Console::WriteLine( "' {0}' is a restricted header", myWebHeaderCollection->AllKeys[ i ] );
      else
               Console::WriteLine( "' {0}' is not a restricted header", myWebHeaderCollection->AllKeys[ i ] );
   }
   myHttpWebResponse->Close();
}
catch ( WebException^ e ) 
{
   Console::WriteLine( "\nWebException is thrown.\nMessage is: {0}", e->Message );
   if ( e->Status == WebExceptionStatus::ProtocolError )
   {
      Console::WriteLine( "Status Code : {0}", (dynamic_cast<HttpWebResponse^>(e->Response))->StatusCode );
      Console::WriteLine( "Status Description : {0}", (dynamic_cast<HttpWebResponse^>(e->Response))->StatusDescription );
      Console::WriteLine( "Server : {0}", (dynamic_cast<HttpWebResponse^>(e->Response))->Server );
   }
}
catch ( Exception^ e ) 
{
   Console::WriteLine( "Exception is thrown. Message is : {0}", e->Message );
}
    try {
        // Create a web request for "www.msn.com".
        HttpWebRequest myHttpWebRequest = (HttpWebRequest) WebRequest.Create("http://www.msn.com");

        // Get the associated response for the above request.
        HttpWebResponse myHttpWebResponse = (HttpWebResponse) myHttpWebRequest.GetResponse();

        // Get the headers associated with the response.
        WebHeaderCollection myWebHeaderCollection = myHttpWebResponse.Headers;
        
        for (int i = 0; i < myWebHeaderCollection.Count;i++)	
        {
        // Check if the first response header is restricted.
        if(WebHeaderCollection.IsRestricted(myWebHeaderCollection.AllKeys[i]))
            Console.WriteLine("'{0}' is a restricted header", myWebHeaderCollection.AllKeys[i]);
        else
            Console.WriteLine("'{0}' is not a restricted header", myWebHeaderCollection.AllKeys[i]);
        }
        myHttpWebResponse.Close();
    }
    catch(WebException e) {
        Console.WriteLine("\nWebException is thrown.\nMessage is:" + e.Message);
        if(e.Status == WebExceptionStatus.ProtocolError) {
            Console.WriteLine("Status Code : {0}", ((HttpWebResponse)e.Response).StatusCode);
            Console.WriteLine("Status Description : {0}", ((HttpWebResponse)e.Response).StatusDescription);
            Console.WriteLine("Server : {0}", ((HttpWebResponse)e.Response).Server);
        }
    }
    catch(Exception e) {
        Console.WriteLine("Exception is thrown. Message is :" + e.Message);
    }

}
Public Shared Sub Main()
Try
        'Create a web request for "www.msn.com".
        Dim myHttpWebRequest As HttpWebRequest = CType(WebRequest.Create("http://www.msn.com"), HttpWebRequest)
        
        'Get the associated response for the above request.
        Dim myHttpWebResponse As HttpWebResponse = CType(myHttpWebRequest.GetResponse(), HttpWebResponse)
        
        'Get the headers associated with the response.
        Dim myWebHeaderCollection As WebHeaderCollection = myHttpWebResponse.Headers
        
        'Check if the first response header is restricted.
    dim i as integer
    for i =0 to myWebHeaderCollection.Count-1
            If WebHeaderCollection.IsRestricted(myWebHeaderCollection.AllKeys(i)) Then
                Console.WriteLine("'{0}' is a restricted header", myWebHeaderCollection.AllKeys(i))
            Else
                Console.WriteLine("'{0}' is not a restricted header", myWebHeaderCollection.AllKeys(i))
            End If 
    next
    myHttpWebResponse.Close()
    Catch e As WebException
        Console.WriteLine(e.Message)
        If e.Status = WebExceptionStatus.ProtocolError Then
            Console.WriteLine("Status Code : {0}", CType(e.Response, HttpWebResponse).StatusCode)
            Console.WriteLine("Status Description : {0}", CType(e.Response, HttpWebResponse).StatusDescription)
            Console.WriteLine("Server : {0}", CType(e.Response, HttpWebResponse).Server)
        End If
    Catch e As Exception
        Console.WriteLine(e.Message)
    End Try
End Sub

備註

方法會傳回,表示要求或回應標頭受到限制,而且必須使用屬性來設定,而不是直接或由系統設定。 true IsRestrictedThe IsRestricted method returns true to indicate that a request or response header is restricted and must be set using properties instead of directly or is set by the system. 限制的標頭為:The restricted headers are:

  • 接受Accept

  • 連線Connection

  • Content-LengthContent-Length

  • Content-TypeContent-Type

  • 日期Date

  • 有望Expect

  • 主機Host

  • 如果-已修改-自起If-Modified-Since

  • RangeRange

  • 推薦者Referer

  • 傳輸-編碼Transfer-Encoding

  • 使用者代理程式User-Agent

  • Proxy-連線Proxy-Connection

適用於