HttpWebRequest.EndGetRequestStream 方法

定义

命名空间:

System.Net

程序集:

System.Net.Requests.dll

结束 Stream 对象用于写入数据的异步请求。

重载

EndGetRequestStream(IAsyncResult, TransportContext)	结束 Stream 对象的异步请求，该请求用于写入数据和输出与流关联的 TransportContext。
EndGetRequestStream(IAsyncResult)	结束 Stream 对象用于写入数据的异步请求。

EndGetRequestStream(IAsyncResult, TransportContext)

Source:

HttpWebRequest.cs

结束 Stream 对象的异步请求，该请求用于写入数据和输出与流关联的 TransportContext。

public:
 System::IO::Stream ^ EndGetRequestStream(IAsyncResult ^ asyncResult, [Runtime::InteropServices::Out] System::Net::TransportContext ^ % context);

public System.IO.Stream EndGetRequestStream (IAsyncResult asyncResult, out System.Net.TransportContext? context);

override this.EndGetRequestStream : IAsyncResult * TransportContext -> System.IO.Stream

Public Function EndGetRequestStream (asyncResult As IAsyncResult, ByRef context As TransportContext) As Stream

参数

asyncResult

IAsyncResult

流挂起的请求。

context

TransportContext

Stream的 TransportContext。

返回

Stream

用于写入请求数据的 Stream。

例外

ArgumentException

当前实例未从调用 BeginGetRequestStream(AsyncCallback, Object)返回 asyncResult。

ArgumentNullException

asyncResult null。

InvalidOperationException

以前使用 asyncResult调用此方法。

IOException

请求未完成，没有可用的流。

WebException

以前调用 Abort()。

-或-

处理请求时出错。

注解

谨慎

WebRequest、HttpWebRequest、ServicePoint和 WebClient 已过时，不应将其用于新开发。 请改用 HttpClient。

EndGetRequestStream 方法完成由 BeginGetRequestStream 方法启动的流的异步请求，并输出与流关联的 TransportContext。 返回 Stream 对象后，可以使用 Stream.Write 方法通过 HttpWebRequest 发送数据。

某些使用集成 Windows 身份验证和扩展保护的应用程序可能需要能够查询 HttpWebRequest 使用的传输层，以便从基础 TLS 通道检索通道绑定令牌（CBT）。 GetRequestStream 方法提供对 HTTP 方法的访问权限，这些方法具有请求正文（POST 和 PUT 请求）。 仅当应用程序实现自己的身份验证并且需要访问 CBT 时，才需要这样做。

注意

• 如果需要在将数据写入流之前设置 ContentLength 属性的值。
• 必须调用 Stream.Close 方法才能关闭流并释放连接以供重复使用。 如果无法关闭流，应用程序将耗尽连接。
• 在应用程序中启用网络跟踪时，此成员将输出跟踪信息。 有关详细信息，请参阅 .NET Framework中的 网络跟踪。

另请参阅

• TransportContext
• GetChannelBinding(ChannelBindingKind)
• System.Security.Authentication.ExtendedProtection
• ChannelBinding
• 使用扩展保护 集成 Windows 身份验证

EndGetRequestStream(IAsyncResult)

Source:

HttpWebRequest.cs

结束 Stream 对象用于写入数据的异步请求。

public:
 override System::IO::Stream ^ EndGetRequestStream(IAsyncResult ^ asyncResult);

public override System.IO.Stream EndGetRequestStream (IAsyncResult asyncResult);

override this.EndGetRequestStream : IAsyncResult -> System.IO.Stream

Public Overrides Function EndGetRequestStream (asyncResult As IAsyncResult) As Stream

参数

asyncResult

IAsyncResult

流挂起的请求。

返回

Stream

用于写入请求数据的 Stream。

例外

ArgumentNullException

asyncResult null。

IOException

请求未完成，没有可用的流。

ArgumentException

当前实例未从调用 BeginGetRequestStream(AsyncCallback, Object)返回 asyncResult。

InvalidOperationException

以前使用 asyncResult调用此方法。

WebException

以前调用 Abort()。

-或-

处理请求时出错。

示例

下面的代码示例使用 EndGetRequestStream 方法结束流实例的异步请求。

#using <System.dll>

using namespace System;
using namespace System::Net;
using namespace System::IO;
using namespace System::Text;
using namespace System::Threading;
ref class HttpWebRequestBeginGetRequest
{
public:
   static ManualResetEvent^ allDone = gcnew ManualResetEvent( false );
   static void Main()
   {
      
      // Create a new HttpWebRequest object.
      HttpWebRequest^ request = dynamic_cast<HttpWebRequest^>(WebRequest::Create( "http://www.contoso.com/example.aspx" ));
      
      // Set the ContentType property.
      request->ContentType = "application/x-www-form-urlencoded";
      
      // Set the Method property to 'POST' to post data to the Uri.
      request->Method = "POST";
      
      // Start the asynchronous operation.    
      AsyncCallback^ del = gcnew AsyncCallback(GetRequestStreamCallback);
      request->BeginGetRequestStream( del, request );
      
      // Keep the main thread from continuing while the asynchronous
      // operation completes. A real world application
      // could do something useful such as updating its user interface. 
      allDone->WaitOne();
    }
      

private:
    static void GetRequestStreamCallback(IAsyncResult^ asynchronousResult)
    {
        HttpWebRequest^ request = dynamic_cast<HttpWebRequest^>(asynchronousResult->AsyncState);
        
        // End the operation
        Stream^ postStream = request->EndGetRequestStream(asynchronousResult);

        Console::WriteLine("Please enter the input data to be posted:");
        String^ postData = Console::ReadLine();

        // Convert the string into a byte array.
        array<Byte>^ByteArray = Encoding::UTF8->GetBytes(postData);

        // Write to the request stream.
        postStream->Write(ByteArray, 0, postData->Length);
        postStream->Close();

        // Start the asynchronous operation to get the response
        AsyncCallback^ del = gcnew AsyncCallback(GetResponseCallback);
        request->BeginGetResponse(del, request);
    }

   static void GetResponseCallback(IAsyncResult^ asynchronousResult)
   {
      HttpWebRequest^ request = dynamic_cast<HttpWebRequest^>(asynchronousResult->AsyncState);

      // End the operation
      HttpWebResponse^ response = dynamic_cast<HttpWebResponse^>(request->EndGetResponse(asynchronousResult));
      Stream^ streamResponse = response->GetResponseStream();
      StreamReader^ streamRead = gcnew StreamReader(streamResponse);
      String^ responseString = streamRead->ReadToEnd();
      Console::WriteLine(responseString);
      // Close the stream object
      streamResponse->Close();
      streamRead->Close();

      // Release the HttpWebResponse
      response->Close();
      allDone->Set();
   }
};

void main()
{
   HttpWebRequestBeginGetRequest::Main();
}

using System;
using System.Net;
using System.IO;
using System.Text;
using System.Threading;

class HttpWebRequestBeginGetRequest
{
    private static ManualResetEvent allDone = new ManualResetEvent(false);

    public static void Main(string[] args)
    {


        // Create a new HttpWebRequest object.
        HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://www.contoso.com/example.aspx");

        request.ContentType = "application/x-www-form-urlencoded";

        // Set the Method property to 'POST' to post data to the URI.
        request.Method = "POST";

        // start the asynchronous operation
        request.BeginGetRequestStream(new AsyncCallback(GetRequestStreamCallback), request);

        // Keep the main thread from continuing while the asynchronous
        // operation completes. A real world application
        // could do something useful such as updating its user interface.
        allDone.WaitOne();
    }

    private static void GetRequestStreamCallback(IAsyncResult asynchronousResult)
    {
        HttpWebRequest request = (HttpWebRequest)asynchronousResult.AsyncState;

        // End the operation
        Stream postStream = request.EndGetRequestStream(asynchronousResult);

        Console.WriteLine("Please enter the input data to be posted:");
        string postData = Console.ReadLine();

        // Convert the string into a byte array.
        byte[] byteArray = Encoding.UTF8.GetBytes(postData);

        // Write to the request stream.
        postStream.Write(byteArray, 0, postData.Length);
        postStream.Close();

        // Start the asynchronous operation to get the response
        request.BeginGetResponse(new AsyncCallback(GetResponseCallback), request);
    }

    private static void GetResponseCallback(IAsyncResult asynchronousResult)
    {
        HttpWebRequest request = (HttpWebRequest)asynchronousResult.AsyncState;

        // End the operation
        HttpWebResponse response = (HttpWebResponse)request.EndGetResponse(asynchronousResult);
        Stream streamResponse = response.GetResponseStream();
        StreamReader streamRead = new StreamReader(streamResponse);
        string responseString = streamRead.ReadToEnd();
        Console.WriteLine(responseString);
        // Close the stream object
        streamResponse.Close();
        streamRead.Close();

        // Release the HttpWebResponse
        response.Close();
        allDone.Set();
    }
}

Imports System.Net
Imports System.IO
Imports System.Text
Imports System.Threading

Class HttpWebRequestBeginGetRequest
    Public Shared allDone As New ManualResetEvent(False)

    Shared Sub Main()


        ' Create a new HttpWebRequest object.
        Dim request As HttpWebRequest = CType(WebRequest.Create("http://www.contoso.com/example.aspx"), _
                 HttpWebRequest)

        ' Set the ContentType property.
        request.ContentType = "application/x-www-form-urlencoded"

        '  Set the Method property to 'POST' to post data to the URI.
        request.Method = "POST"

        ' Start the asynchronous operation.		
        Dim result As IAsyncResult = _
            CType(request.BeginGetRequestStream(AddressOf GetRequestStreamCallback, request), _
            IAsyncResult)

        ' Keep the main thread from continuing while the asynchronous
        ' operation completes. A real world application
        ' could do something useful such as updating its user interface. 
        allDone.WaitOne()
    End Sub

    Private Shared Sub GetRequestStreamCallback(ByVal asynchronousResult As IAsyncResult)
        Dim request As HttpWebRequest = CType(asynchronousResult.AsyncState, HttpWebRequest)
        
        ' End the operation
        Dim postStream As Stream = request.EndGetRequestStream(asynchronousResult)
        Console.WriteLine("Please enter the input data to be posted:")
        Dim postData As [String] = Console.ReadLine()
        
        '  Convert the string into byte array.
        Dim byteArray As Byte() = Encoding.UTF8.GetBytes(postData)

        ' Write to the stream.
        postStream.Write(byteArray, 0, postData.Length)
        postStream.Close()

        ' Start the asynchronous operation to get the response
        Dim result As IAsyncResult = _
            CType(request.BeginGetResponse(AddressOf GetResponseCallback, request), _
            IAsyncResult)
    End Sub

    Private Shared Sub GetResponseCallback(ByVal asynchronousResult As IAsyncResult)
        Dim request As HttpWebRequest = CType(asynchronousResult.AsyncState, HttpWebRequest)
        
        '  Get the response.
        Dim response As HttpWebResponse = CType(request.EndGetResponse(asynchronousResult), _
           HttpWebResponse)
        
        Dim streamResponse As Stream = response.GetResponseStream()
        Dim streamRead As New StreamReader(streamResponse)
        Dim responseString As String = streamRead.ReadToEnd()
        
        Console.WriteLine(responseString)
        
        ' Close Stream object.
        streamResponse.Close()
        streamRead.Close()

        ' Release the HttpWebResponse.
        allDone.Set()
        response.Close()
    End Sub
            
End Class

注解

谨慎

WebRequest、HttpWebRequest、ServicePoint和 WebClient 已过时，不应将其用于新开发。 请改用 HttpClient。

EndGetRequestStream 方法为 BeginGetRequestStream 方法启动的流完成异步请求。 返回 Stream 对象后，可以使用 Stream.Write 方法通过 HttpWebRequest 发送数据。

注意

• 在将数据写入流之前，必须设置 ContentLength 属性的值。
• 必须调用 Stream.Close 方法才能关闭流并释放连接以供重复使用。 如果无法关闭流，应用程序将耗尽连接。
• 在应用程序中启用网络跟踪时，此成员将输出跟踪信息。 有关详细信息，请参阅 .NET Framework中的 网络跟踪。