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How to get async result in main thread

I'm making a login page on Windows Phone 7 app. I'd like to get login error status code on the login page when login error message return from server on async thread.

So my question is : In bellow code sample, please let me know how do you get "responseString(string)" in Main method?

http://msdn.microsoft.com/en-us/library/system.net.httpwebrequest.begingetrequeststream.aspx

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();

        /* I'd like to get "responseString" here. */
    }

    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(); /* I'd like to get this responseString in Main method. */
        Console.WriteLine(responseString);
        // Close the stream object
        streamResponse.Close();
        streamRead.Close();

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


You could just define responseString as a class-level variable instead of defining it within the GetResponseCallback method. That way, it can be accessed from anywhere in the class, rather than just the method scope.

To navigate to another page from a background thread, you can use a Dispatcher.

    //Method to move to next page. Can be called from GetResponseCallBack
    private void NavigateToNextPage()
    {
        Dispatcher.BeginInvoke(() =>
        {
           NavigationService.Navigate(new Uri("Page2.xaml", UriKind.Relative"));
        });
    }
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