【原创】C#使用HttpWebRequest，HttpWebResponse

HttpWebRequest类：提供WebRequest类的Http特定的实现。HttpWebRequest 类对 WebRequest 中定义的属性和方法提供支持，也对使用户能够直接与使用 HTTP 的服务器交互的附加属性和方法提供支持。   

        /// <summary>
        /// 创建 HttpWebRequest
        /// </summary>
        /// <returns>HttpWebRequest</returns>
        public HttpWebRequest Create(string url,string name,string password)
        {

            //创建HttpWebRequest  实例，使用WebRequest.Create
            HttpWebRequest webRequest = (HttpWebRequest)WebRequest.Create(url);
            //发送请求
            webRequest.Method = "POST";
            //编码
            webRequest.ContentType = "text/xml;charset=UTF-8";
            //访问凭证
            webRequest.Credentials = new NetworkCredential(name, password);
            //设置代理,如不需要代理，以下代码不需要
            string Isproxy = "代理ip";
            string proxyName = “代理访问用户”;
            string proxyPassword = “代理访问密码”;
            if (!string.IsNullOrEmpty(Isproxy))
            {
                WebProxy myProxy = new WebProxy(Isproxy , true);
                myProxy.Credentials = new NetworkCredential(proxyName , proxyPassword , "ip");
                webRequest.Proxy = Isproxy ;
            }
            return webRequest;
        }

提示：HttpWebRequest对象有一些相关设置属性，如Method(发送方式),TimeOut(请求超时时间),ContentType(Http标头的值)等等。不要使用构造函数创建HttpWebRequest实例，应使用WebRequest.Create(URI uriString)来创建实例，如果URI是Http://或Https://， 返回的是HttpWebRequest对象。(建立请求特定URI的对象) 当向资源发送数据时，GetRequestStream方法返回用于发送数据的Stream对象。

        /// <summary>
        /// <param name="value">发送数据</param>
        /// </summary>
        /// <returns>返回数据</returns>
        public string ResponseXML(string url,string name,string password,string value)
        {
            string result = "";
            //创建服务
            HttpWebRequest webRequest = Create(url,name,password);
            //字符转字节
            byte[] bytes = Encoding.UTF8.GetBytes(value);
            Stream writer = webRequest.GetRequestStream();
            writer.Write(bytes, 0, bytes.Length);
            writer.Flush();
            writer.Close();
            //返回 HttpWebResponse
            HttpWebResponse hwRes= webRequest.GetResponse() as HttpWebResponse;
            if (hwRes.StatusCode == System.Net.HttpStatusCode.OK)
            {//是否返回成功
                Stream rStream = hwRes.GetResponseStream();
                //流读取
                StreamReader sr = new StreamReader(rStream, Encoding.UTF8);
                result = sr.ReadToEnd();
                sr.Close();
                rStream.Close();
            }
            else
            {
                result = "连接错误";
            }

           //关闭
            hwRes.Close();
            return result;
        }