谁能告诉我这个简单的代码我做错了什么?当我运行它时,它会挂起
using (Stream postStream = request.EndGetRequestStream(asynchronousResult))
如果我注释掉 requestState.Wait.WaitOne(); 行代码正确执行但显然不等待响应。我猜对 EndGetRequestStream 的调用以某种方式将我返回到主线程的上下文?我很确定我的代码与示例基本相同(MSDN 文档)
using System;
using System.Net;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.IO;
using System.Text;
namespace SBRemoteClient
{
public class JSONClient
{
public string ExecuteJSONQuery(string url, string query)
{
System.Uri uri = new Uri(url);
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
request.Method = "POST";
request.Accept = "application/json";
byte[] requestBytes = Encoding.UTF8.GetBytes(query);
RequestState requestState = new RequestState(request, requestBytes);
IAsyncResult resultRequest = request.BeginGetRequestStream(new AsyncCallback(GetRequestStreamCallback), requestState);
requestState.Wait.WaitOne();
IAsyncResult resultResponse = (IAsyncResult)request.BeginGetResponse(new AsyncCallback(GetResponseStreamCallback), requestState);
requestState.Wait.WaitOne();
return requestState.Response;
}
private static void GetRequestStreamCallback(IAsyncResult asynchronousResult)
{
try
{
RequestState requestState = (RequestState)asynchronousResult.AsyncState;
HttpWebRequest request = requestState.Request;
using (Stream postStream = request.EndGetRequestStream(asynchronousResult))
{
postStream.Write(requestState.RequestBytes, 0, requestState.RequestBytes.Length);
}
requestState.Wait.Set();
}
catch (Exception e) {
Console.Out.WriteLine(e);
}
}
private static void GetResponseStreamCallback(IAsyncResult asynchronousResult)
{
RequestState requestState = (RequestState)asynchronousResult.AsyncState;
HttpWebRequest request = requestState.Request;
using (HttpWebResponse response = (HttpWebResponse)request.EndGetResponse(asynchronousResult))
{
using (Stream responseStream = response.GetResponseStream())
{
using (StreamReader streamRead = new StreamReader(responseStream))
{
requestState.Response = streamRead.ReadToEnd();
requestState.Wait.Set();
}
}
}
}
}
}