.NET 网页或json数据抓取系列：1 - 发送请求

1. 创建HttpWebRequest 发送请求，添加Headers信息，例如User-Agent, token, Authorization

 var client = (HttpWebRequest)WebRequest.Create(new Uri(url));
 client.Method = method; //Post或者Get
 client.Headers.Add("User-Agent", "Mozilla/5.0 (Windows NT 6.1; Win64; x64; rv:50.0) Gecko/20100101 Firefox/50.0");
 client.Headers.Add("token", token);
 client.Headers.Add("Authorization", "Bearer eyJ......");

2.  添加cookie到request, 例如UserInfo

 client.CookieContainer.Add(new Cookie("UserInfo", "88FF5A5F6292DD26A76667653A992991B47B", client.RequestUri.LocalPath,   client.RequestUri.Host));

3. 添加Post数据到request

 var strJson = Newtonsoft.Json.JsonConvert.SerializeObject(data);
 if (data != null && !string.IsNullOrEmpty(strJson))
 {
    byte[] jsonData = Encoding.UTF8.GetBytes(strJson);
    client.ContentLength = jsonData.Le