[C#]Http异步请求

在WinForm设计中，如果直接使用Http请求会导致UI等待Http请求返回而出现界面假死现象。

所以我们可以使用异步的Http请求来解决这个问题。

1.    设置请求类型并发送请求的方法HttpPost:

    public static void HttpPost(string Url)
        {
            try
            {
                HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url）;
 
                request.Method = "POST";//这里是POST请求，可以改成GET
                request.ContentType = "application/x-www-form-urlencoded";
                request.BeginGetResponse(new AsyncCallback(Compleate), request);
            }
            catch
            {
                MessageBox.Show("请求失败.");
            }
        }

2.异步接收返回结果的方法Compleate：

        public static void Compleate(IAsyncResult asyncResult)
        {
            try
            {
                HttpWebRequest req = (asyncResult.AsyncState as HttpWebRequest);
                HttpWebResponse res = req.EndGetResponse(asyncResult) as HttpWebResponse;
                StreamReader reader = new StreamReader(res.GetResponseStream());

                MessageBox.Show(reader.ReadToEnd());
            }
            catch
            {
                MessageBox.Show("获取失败.");
            }
        }