C# 发送Post请求如何设置请求头和请求体？

代码参考下：

private  void SetHeaderValue(WebHeaderCollection header, string name, string value)
            {
                var property = typeof(WebHeaderCollection).GetProperty("InnerCollection",BindingFlags.Instance | BindingFlags.NonPublic);
                if (property != null)
                    {
                        var collection = property.GetValue(header, null) as NameValueCollection;
                        collection[name] = value;
                    }
            }


            public  void webHttpResponse(string url)
            {

                Encoding gb2312 = Encoding.GetEncoding("GB2312");
                //创建连接
                HttpWebRequest httpRequest = (HttpWebRequest)HttpWebRequest.Create(url);

                SetHeaderValue(httpRequest.Headers, "AppCode", "XXX");
                SetHeaderValue(httpRequest.Headers, "token", "abc12345678");

                //发送请求的方式
                httpRequest.Method = "POST";
                //发送的协议
                httpRequest.Accept = "HTTP";

                string param = "factory=factory888&position=00006789";
                byte[] bs = Encoding.ASCII.GetBytes(param);

                httpRequest.ContentType = "application/x-www-form-urlencoded";
                httpRequest.ContentLength = bs.Length;
                using (Stream reqStream = httpRequest.GetRequestStream())
                {
                    reqStream.Write(bs, , bs.Length);
                    reqStream.Close();
                }

                httpRequest.CookieContainer = new CookieContainer();

                //创建一个响应对象
                using (HttpWebResponse httpResponse = (HttpWebResponse)httpRequest.GetResponse())
                {
                    if (httpResponse.StatusDescription == "OK")
                    {
                        //passed = httpRequest.Address.AbsolutePath.Contains("Index");
                        passed = true;
                    }
                    else
                    {
                        passed = false;
                    }
                    httpResponse.Close();
                }
            }

https://www.24kplus.com/csharp/1157.html