C#通过WebClient/HttpWebRequest实现http的post/get方法

WebClient和HttpWebRequst 是用来获取数据的2种方式，一般而言，WebClient更倾向于“按需下载”，事实上掌握它也是相对容易的，而HttpWebRequst则允许你设置 请求头或者对内容需要更多的控制，后者有点类似于form中的submit。虽然两者都是异步请求事件，但是WebClient是基于事件的异步，而 HttpWebRequst是基于代理的异步编程

WebClient封装了一下便于使用，但是需要稍微细节一些的操作的时候，就得用WebResponse和WebRequest来操作了。比如要 想控制TCP链接数，自定义HTTP请求头或者Post自定义数据等等,HTTPWebRequest是专用于HTTP协议的WebRequest，想要 灵活性选择后者，简单性选择前者，2.0里提供了FtpWebResponse...FileWebResponse,用起来可能选择范围更广点。

 

//body是要传递的参数,格式"roleId=1&uid=2"
//post的cotentType填写:
//"application/x-www-form-urlencoded"
//soap填写:"text/xml; charset=utf-8"
    public static string PostHttp(string url, string body, string contentType)
    {
        HttpWebRequest httpWebRequest = (HttpWebRequest)WebRequest.Create(url);

        httpWebRequest.ContentType = contentType;
        httpWebRequest.Method = "POST";
        httpWebRequest.Timeout = 20000;

        byte[] btBodys = Encoding.UTF8.GetBytes(body);
        httpWebRequest.ContentLength = btBodys.Length;
        httpWebRequest.GetRequestStream().Write(btBodys, 0, btBodys.Length);

        HttpWebResponse httpWebResponse = (HttpWebResponse)httpWebRequest.GetResponse();
        StreamReader streamReader = new StreamReader(httpWebResponse.GetResponseStream());
        string responseContent = streamReader.ReadToEnd();

        httpWebResponse.Close();
        streamReader.Close();
        httpWebRequest.Abort();
        httpWebResponse.Close();

        return responseContent;
    }

POST方法(httpWebRequest)

 

/// <summary>
        /// 通过WebClient类Post数据到远程地址，需要Basic认证；
        /// 调用端自己处理异常
        /// </summary>
        /// <param name="uri"></param>
        /// <param name="paramStr">name=张三&age=20</param>
        /// <param name="encoding">请先确认目标网页的编码方式</param>
        /// <param name="username"></param>
        /// <param name="password"></param>
        /// <returns></returns>
        public static string Request_WebClient(string uri, string paramStr, Encoding encoding, string username, string password)
        {
            if (encoding == null)
                encoding = Encoding.UTF8;

            string result = string.Empty;

            WebClient wc = new WebClient();

            // 采取POST方式必须加的Header
            wc.Headers.Add("Content-Type", "application/x-www-form-urlencoded");

            byte[] postData = encoding.GetBytes(paramStr);

            if (!string.IsNullOrEmpty(username) && !string.IsNullOrEmpty(password))
            {
                wc.Credentials = GetCredentialCache(uri, username, password);
                wc.Headers.Add("Authorization", GetAuthorization(username, password));
            }

            byte[] responseData = wc.UploadData(uri, "POST", postData); // 得到返回字符流
            return encoding.GetString(responseData);// 解码                  
        }

POST方法(WebClient)

public static string GetHttp(string url, HttpContext httpContext)
    {
        string queryString = "?";

        foreach (string key in httpContext.Request.QueryString.AllKeys)
        {
            queryString += key + "=" + httpContext.Request.QueryString[key] + "&";
        }

        queryString = queryString.Substring(0, queryString.Length - 1);

        HttpWebRequest httpWebRequest = (HttpWebRequest)WebRequest.Create(url + queryString);

        httpWebRequest.ContentType = "application/json";
        httpWebRequest.Method = "GET";
        httpWebRequest.Timeout = 20000;

        //byte[] btBodys = Encoding.UTF8.GetBytes(body);
        //httpWebRequest.ContentLength = btBodys.Length;
        //httpWebRequest.GetRequestStream().Write(btBodys, 0, btBodys.Length);

        HttpWebResponse httpWebResponse = (HttpWebResponse)httpWebRequest.GetResponse();
        StreamReader streamReader = new StreamReader(httpWebResponse.GetResponseStream());
        string responseContent = streamReader.ReadToEnd();

        httpWebResponse.Close();
        streamReader.Close();

        return responseContent;
    }

Get方法(HttpWebRequest)

/// <summary>
        /// 通过 WebRequest/WebResponse 类访问远程地址并返回结果，需要Basic认证；
        /// 调用端自己处理异常
        /// </summary>
        /// <param name="uri"></param>
        /// <param name="timeout">访问超时时间，单位毫秒；如果不设置超时时间，传入0</param>
        /// <param name="encoding">如果不知道具体的编码，传入null</param>
        /// <param name="username"></param>
        /// <param name="password"></param>
        /// <returns></returns>
        public static string Request_WebRequest(string uri, int timeout, Encoding encoding, string username, string password)
        {
            string result = string.Empty;

            WebRequest request = WebRequest.Create(new Uri(uri));

            if (!string.IsNullOrEmpty(username) && !string.IsNullOrEmpty(password))
            {
                request.Credentials = GetCredentialCache(uri, username, password);
                request.Headers.Add("Authorization", GetAuthorization(username, password));
            }

            if (timeout > 0)
                request.Timeout = timeout;

            WebResponse response = request.GetResponse();
            Stream stream = response.GetResponseStream();
            StreamReader sr = encoding == null ? new StreamReader(stream) : new StreamReader(stream, encoding);

            result = sr.ReadToEnd();

            sr.Close();
            stream.Close();

            return result;
        }

        #region # 生成 Http Basic 访问凭证 #

        private static CredentialCache GetCredentialCache(string uri, string username, string password)
        {
            string authorization = string.Format("{0}:{1}", username, password);

            CredentialCache credCache = new CredentialCache();
            credCache.Add(new Uri(uri), "Basic", new NetworkCredential(username, password));

            return credCache;
        }

        private static string GetAuthorization(string username, string password)
        {
            string authorization = string.Format("{0}:{1}", username, password);

            return "Basic " + Convert.ToBase64String(new ASCIIEncoding().GetBytes(authorization));
        }

        #endregion

basic验证的WebRequest/WebResponse

 

json转泛型

 //string _JsonText = System.IO.File.ReadAllText(@"C:\2.TXT");

            //List<Test> _Test = new List<Test>();

            //DataContractJsonSerializer _Json = new DataContractJsonSerializer(_Test.GetType());
            //byte[] _Using = System.Text.Encoding.UTF8.GetBytes(_JsonText);
            //System.IO.MemoryStream _MemoryStream = new System.IO.MemoryStream(_Using);
            //_MemoryStream.Position = 0;

            //_Test = (List<Test>)_Json.ReadObject(_MemoryStream);