c#后台直接发起http请求

 /// <summary>    /// 操作方法    /// </summary>    public class GetHttpHelper {        private static readonly string DefaultUserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.50727)";        /// <summary>        /// Get方法获取Json数据        /// </summary>        /// <param name="url"></param>        /// <returns></returns>        public static string GetHttpResponseJson(string url, IWebProxy webProxy)        {            string json = string.Empty;            Encoding encoding = Encoding.UTF8;            HttpWebResponse Response = CreateGetHttpResponse(new HttpGetParametersModel()            {                Url = url,                WebProxy = webProxy            });            json = GetStream(Response, encoding);            return json;        }        /// <summary>        /// 创建GET方式的HTTP请求        /// </summary>        /// <param name="url">请求的URL</param>        /// <param name="timeout">请求的超时时间</param>        /// <param name="userAgent">请求的客户端浏览器信息，可以为空</param>        /// <param name="cookies">随同HTTP请求发送的Cookie信息，如果不需要身份验证可以为空</param>        /// <returns></returns>        public static HttpWebResponse CreateGetHttpResponse(HttpGetParametersModel getParametersModel)        {            if (string.IsNullOrEmpty(getParametersModel.Url))            {                throw new ArgumentNullException("getParametersModel.Url");            }            HttpWebRequest request = WebRequest.Create(getParametersModel.Url) as HttpWebRequest;            if (getParametersModel.WebProxy != null)            {                request.Proxy = getParametersModel.WebProxy;            }            request.Method = "GET";            request.UserAgent = DefaultUserAgent;            if (!string.IsNullOrEmpty(getParametersModel.UserAgent))            {                request.UserAgent = getParametersModel.UserAgent;            }            if (getParametersModel.Timeout.HasValue)            {                request.Timeout = getParametersModel.Timeout.Value;            }            if (getParametersModel.Cookies != null)            {                request.CookieContainer = new CookieContainer();                request.CookieContainer.Add(getParametersModel.Cookies);            }            return request.GetResponse() as HttpWebResponse;        }        /// <summary>        /// 将response转换成文本        /// </summary>        /// <param name="response"></param>        /// <param name="encoding"></param>        /// <returns></returns>        private static string GetStream(HttpWebResponse response, Encoding encoding)        {            try            {                if (response.StatusCode == HttpStatusCode.OK)                {                    switch (response.ContentEncoding.ToLower())                    {                        case "gzip":                            {                                string result = Decompress(response.GetResponseStream(), encoding);                                response.Close();                                return result;                            }                        default:                            {                                using (StreamReader sr = new StreamReader(response.GetResponseStream(), encoding))                                {                                    string result = sr.ReadToEnd();                                    sr.Close();                                    sr.Dispose();                                    response.Close();                                    return result;                                }                            }                    }                }                else                {                    response.Close();                }            }            catch (Exception e)            {                throw e;            }            return "";        }        private static string Decompress(Stream stream, Encoding encoding)        {            byte[] buffer = new byte[100];            //int length = 0;            using (GZipStream gz = new GZipStream(stream, CompressionMode.Decompress))            {                //GZipStream gzip = new GZipStream(res.GetResponseStream(), CompressionMode.Decompress);                using (StreamReader reader = new StreamReader(gz, encoding))                {                    return reader.ReadToEnd();                }            }        }    }    #region GET/POST请求参数模型    /// <summary>    /// GET请求参数模型    /// </summary>    public class HttpGetParametersModel    {        /// <summary>        /// 请求的URL(GET方式就附加参数)        /// </summary>        public string Url { get; set; }        /// <summary>        /// 超时时间        /// </summary>        public int? Timeout { get; set; }        /// <summary>        ///浏览器代理类型        /// </summary>        public string UserAgent { get; set; }        /// <summary>        /// Web请求代理        /// </summary>        public IWebProxy WebProxy { get; set; }        /// <summary>        /// Cookies列表        /// </summary>        public CookieCollection Cookies { get; set; }    }    /// <summary>    /// POST请求参数模型    /// </summary>    public class HttpPostParametersModel : HttpGetParametersModel    {        /// <summary>        /// POST参数字典        /// </summary>        public IDictionary<string, string> DictParameters { get; set; }        /// <summary>        /// 发送HTTP请求时所用的编码        /// </summary>        public Encoding RequestEncoding { get; set; }    }    #endregion GET/POST请求参数模型

调用方式：

        try        {            string url = " http://music.163.com/api/playlist/detail?id=58451795";         object obj=  GetHttpResponseJson(url, null);        }        catch (Exception e)        {        }