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HttpWebRequest.EndGetRequestStream Method (IAsyncResult)

Ends an asynchronous request for a Stream object to use to write data.

Namespace:  System.Net
Assembly:  System (in System.dll)

'Declaration
Public Overrides Function EndGetRequestStream ( _
	asyncResult As IAsyncResult _
) As Stream
'Usage
Dim instance As HttpWebRequest 
Dim asyncResult As IAsyncResult 
Dim returnValue As Stream 

returnValue = instance.EndGetRequestStream(asyncResult)

Parameters

asyncResult
Type: System.IAsyncResult

The pending request for a stream.

Return Value

Type: System.IO.Stream
A Stream to use to write request data.

ExceptionCondition
ArgumentNullException

asyncResult is Nothing.

IOException

The request did not complete, and no stream is available.

ArgumentException

asyncResult was not returned by the current instance from a call to BeginGetRequestStream.

InvalidOperationException

This method was called previously using asyncResult.

WebException

Abort was previously called.

-or-

An error occurred while processing the request.

The EndGetRequestStream method completes an asynchronous request for a stream that was started by the BeginGetRequestStream method. After the Stream object has been returned, you can send data with the HttpWebRequest by using the Stream.Write method.

NoteNote:

You must set the value of the ContentLength property before writing data to the stream.

Caution noteCaution:

You must call the Stream.Close method to close the stream and release the connection for reuse. Failure to close the stream causes your application to run out of connections.

NoteNote:

This member outputs trace information when you enable network tracing in your application. For more information, see Network Tracing.

The following code example uses the EndGetRequestStream method to end an asynchronous request for a stream instance.

Imports System
Imports System.Net
Imports System.IO
Imports System.Text
Imports System.Threading
Imports Microsoft.VisualBasic

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 ' Main

    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 ' ReadRequestStreamCallback

    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 ' ReadResponseCallback

End Class ' HttpWebRequest_BeginGetRequest
#using <mscorlib.dll>
#using <System.dll>
using namespace System;
using namespace System::Net;
using namespace System::IO;
using namespace System::Text;
using namespace System::Threading;

__gc class HttpWebRequestBeginGetRequest {
public:
   static ManualResetEvent* allDone = new ManualResetEvent(false);

public:
	static void Main() {

        // Create a new HttpWebRequest object.
        HttpWebRequest* request =
    dynamic_cast<HttpWebRequest*> (WebRequest::Create(S"http://www.contoso.com/example.aspx"));
        // Set the ContentType property.
        request->ContentType=S"application/x-www-form-urlencoded";
        // Set the Method property to 'POST' to post data to the Uri.
        request->Method=S"POST";

        // Start the asynchronous operation.    
		AsyncCallback* del = 	new AsyncCallback(0,ReadCallback);
        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();
        HttpWebResponse* response =
        dynamic_cast<HttpWebResponse*>(request->GetResponse());
        Stream* streamResponse =
        response->GetResponseStream();
        StreamReader* streamRead = new StreamReader(streamResponse);
        String *responseString = streamRead->ReadToEnd();
		Console::WriteLine(responseString);
        // Close Stream object.
        streamResponse->Close();
        streamRead->Close();

        // Release the HttpWebResponse.
        response->Close();
   }
private:
   static void ReadCallback(IAsyncResult* asynchronousResult) 
   {
         HttpWebRequest * request =
            dynamic_cast<HttpWebRequest*> (asynchronousResult->AsyncState);
		 // End the operation.
         Stream* postStream = request->EndGetRequestStream(asynchronousResult);
         Console::WriteLine(S"Please enter the input data to be posted:");
         String * postData = Console::ReadLine();

         // Convert the string into Byte array.
		 Byte ByteArray[] = Encoding::UTF8->GetBytes(postData);
         // Write to the request stream.
         postStream->Write(ByteArray, 0, postData->Length);
         postStream->Close();
         allDone->Set();

   }

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

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 3.5, 2.0, 1.0

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