asp.net - 将参数传递给 BeginGetRequestStream

Question

我正在使用线程池调用一些异步 Web 请求调用来发布数据

我在 for 循环中调用 RunWebAccess 函数

public void RunWebAccess (string strdara, int inttype)
{
     HttpWebRequest req = 
         (HttpWebRequest)WebRequest.Create("http://www.test.com");           
     byte[] requestBytes = System.Text.Encoding.ASCII.GetBytes(xmlvar);
     req.Method = "POST";
     req.ContentType = "text/xml";
     req.ContentLength = requestBytes.Length;         
     IAsyncResult result = 
         req.BeginGetRequestStream(new AsyncCallback(ProcessResults), req);
}

private void ProcessResults(IAsyncResult result)
{ 
    HttpWebRequest request = (HttpWebRequest)result.AsyncState;
    Stream postStream = request.EndGetRequestStream(result);
    postStream.Write(result., 0, postData.Length ;
    postStream.Close();
}

处理结果 函数不起作用，因为它无法访问参数。

问题是我想在 ProcessResults 函数中传递参数并写入流。

根据代码，我不能在 ProcessResults 函数中使用全局变量或读取输入。
(我想在 ProcessResults 函数中传递 strdara,inttype )

Answer 1

您可以对回调使用 lambda 表示法，如下所示:

public void RunWebAccess (string strdara, int inttype)
{
     HttpWebRequest req = 
         (HttpWebRequest)WebRequest.Create("http://www.test.com");           
     byte[] requestBytes = System.Text.Encoding.ASCII.GetBytes(xmlvar);
     req.Method = "POST";
     req.ContentType = "text/xml";
     req.ContentLength = requestBytes.Length;
     IAsyncResult result = null;
     result = 
         req.BeginGetRequestStream(ar =>
         {
            Stream postStream = request.EndGetRequestStream(result);
            postStream.Write(result., 0, postData.Length ;
            postStream.Close();
         }
         , req);
}