HttpWebRequest.MaximumResponseHeadersLength Свойство

Определение

Возвращает или задает максимальную допустимую длину заголовков ответов.Gets or sets the maximum allowed length of the response headers.

public:
 property int MaximumResponseHeadersLength { int get(); void set(int value); };
public int MaximumResponseHeadersLength { get; set; }
member this.MaximumResponseHeadersLength : int with get, set
Public Property MaximumResponseHeadersLength As Integer

Значение свойства

Int32

Длина заголовков ответов, выраженная в килобайтах (1024 байта).The length, in kilobytes (1024 bytes), of the response headers.

Исключения

Свойство установлено уже после отправки запроса.The property is set after the request has already been submitted.

Значение меньше нуля и не равно –1.The value is less than 0 and is not equal to -1.

Примеры

В следующем примере кода задается значение этого свойства.The following code example sets the value of this property.

#using <System.dll>

using namespace System;
using namespace System::Net;
using namespace System::Text;
using namespace System::IO;

// Specify the URL to receive the request.
int main()
{
   array<String^>^args = Environment::GetCommandLineArgs();
   HttpWebRequest^ request = dynamic_cast<HttpWebRequest^>(WebRequest::Create( args[ 1 ] ));
   
   // Set some reasonable limits on resources used by this request
   request->MaximumAutomaticRedirections = 4;
   request->MaximumResponseHeadersLength = 4;
   
   // Set credentials to use for this request.
   request->Credentials = CredentialCache::DefaultCredentials;
   HttpWebResponse^ response = dynamic_cast<HttpWebResponse^>(request->GetResponse());
   Console::WriteLine( "Content length is {0}", response->ContentLength );
   Console::WriteLine( "Content type is {0}", response->ContentType );
   
   // Get the stream associated with the response.
   Stream^ receiveStream = response->GetResponseStream();
   
   // Pipes the stream to a higher level stream reader with the required encoding format. 
   StreamReader^ readStream = gcnew StreamReader( receiveStream,Encoding::UTF8 );
   Console::WriteLine( "Response stream received." );
   Console::WriteLine( readStream->ReadToEnd() );
   response->Close();
   readStream->Close();
}

/*
The output from this example will vary depending on the value passed into Main 
but will be similar to the following:

Content length is 1542
Content type is text/html; charset=utf-8
Response stream received.
<html>
...
</html>

*/
using System;
using System.Net;
using System.Text;
using System.IO;

    public class Test
    {
        // Specify the URL to receive the request.
        public static void Main (string[] args)
        {
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create (args[0]);

            // Set some reasonable limits on resources used by this request
            request.MaximumAutomaticRedirections = 4;
            request.MaximumResponseHeadersLength = 4;
            // Set credentials to use for this request.
            request.Credentials = CredentialCache.DefaultCredentials;
            HttpWebResponse response = (HttpWebResponse)request.GetResponse ();

            Console.WriteLine ("Content length is {0}", response.ContentLength);
            Console.WriteLine ("Content type is {0}", response.ContentType);

            // Get the stream associated with the response.
            Stream receiveStream = response.GetResponseStream ();

            // Pipes the stream to a higher level stream reader with the required encoding format.
            StreamReader readStream = new StreamReader (receiveStream, Encoding.UTF8);

            Console.WriteLine ("Response stream received.");
            Console.WriteLine (readStream.ReadToEnd ());
            response.Close ();
            readStream.Close ();
        }
    }

/*
The output from this example will vary depending on the value passed into Main
but will be similar to the following:

Content length is 1542
Content type is text/html; charset=utf-8
Response stream received.
<html>
...
</html>

*/
Imports System.Net
Imports System.Text
Imports System.IO


    Public Class Test

        ' Specify the URL to receive the request.
        Public Shared Sub Main(ByVal args() As String)
        Dim request As HttpWebRequest = CType(WebRequest.Create(args(0)), HttpWebRequest)


        ' Set some reasonable limits on resources used by this request
        request.MaximumAutomaticRedirections = 4
        request.MaximumResponseHeadersLength = 4

        ' Set credentials to use for this request.
        request.Credentials = CredentialCache.DefaultCredentials

        Dim response As HttpWebResponse = CType(request.GetResponse(), HttpWebResponse)

        Console.WriteLine("Content length is {0}", response.ContentLength)
        Console.WriteLine("Content type is {0}", response.ContentType)

        ' Get the stream associated with the response.
        Dim receiveStream As Stream = response.GetResponseStream()

        ' Pipes the stream to a higher level stream reader with the required encoding format. 
        Dim readStream As New StreamReader(receiveStream, Encoding.UTF8)

        Console.WriteLine("Response stream received.")
        Console.WriteLine(readStream.ReadToEnd())
        response.Close()
        readStream.Close()
    End Sub
End Class
'
'The output from this example will vary depending on the value passed into Main 
'but will be similar to the following:
'
'Content length is 1542
'Content type is text/html; charset=utf-8
'Response stream received.
'...
'
'

Комментарии

Длина заголовка ответа включает строку состояния ответа и все дополнительные управляющие символы, полученные как часть протокола HTTP.The length of the response header includes the response status line and any extra control characters that are received as part of HTTP protocol. Значение-1 означает, что в заголовках ответа ограничение не наложено; значение 0 означает, что все запросы завершаются ошибкой.A value of -1 means no limit is imposed on the response headers; a value of 0 means that all requests fail.

Если MaximumResponseHeadersLength свойство не задано явно, по умолчанию используется значение DefaultMaximumResponseHeadersLength Свойства.If the MaximumResponseHeadersLength property is not explicitly set, it defaults to the value of the DefaultMaximumResponseHeadersLength property.

Если длина полученного заголовка ответа превышает значение MaximumResponseHeadersLength свойства, то EndGetResponse GetResponse методы или будут вызывать исключение WebException со Status свойством, имеющим значение MessageLengthLimitExceeded .If the length of the response header received exceeds the value of the MaximumResponseHeadersLength property, the EndGetResponse or GetResponse methods will throw a WebException with the Status property set to MessageLengthLimitExceeded.

Применяется к