zoukankan      html  css  js  c++  java

  • C#模拟http 发送post或get请求

    C#模拟http 发送post或get请求
    ?
    1
    2
    3
    4
    5
    6
    7
    8
    9
    10
    11
    12
    13
    14
    15
    16
    17
    18
    19
    20
    21
    22
    23
    24
    25
    26
    27
    28
    29
    30
    31
    32
    33
    34
    35
    36
    37
    38
    39
    private string HttpPost(string Url, string postDataStr)
            {
                HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url);
                request.Method = "POST";
                request.ContentType = "application/x-www-form-urlencoded";
                request.ContentLength = Encoding.UTF8.GetByteCount(postDataStr);
                request.CookieContainer = cookie;
                Stream myRequestStream = request.GetRequestStream();
                StreamWriter myStreamWriter = new StreamWriter(myRequestStream, Encoding.GetEncoding("gb2312"));
                myStreamWriter.Write(postDataStr);
                myStreamWriter.Close();
     
                HttpWebResponse response = (HttpWebResponse)request.GetResponse();
     
                response.Cookies = cookie.GetCookies(response.ResponseUri);
                Stream myResponseStream = response.GetResponseStream();
                StreamReader myStreamReader = new StreamReader(myResponseStream, Encoding.GetEncoding("utf-8"));
                string retString = myStreamReader.ReadToEnd();
                myStreamReader.Close();
                myResponseStream.Close();
     
                return retString;
            }
     
            public string HttpGet(string Url, string postDataStr)
            {
                HttpWebRequest request = (HttpWebRequest)WebRequest.Create(Url + (postDataStr == "" ? "" : "?") + postDataStr);
                request.Method = "GET";
                request.ContentType = "text/html;charset=UTF-8";
     
                HttpWebResponse response = (HttpWebResponse)request.GetResponse();
                Stream myResponseStream = response.GetResponseStream();
                StreamReader myStreamReader = new StreamReader(myResponseStream, Encoding.GetEncoding("utf-8"));
                string retString = myStreamReader.ReadToEnd();
                myStreamReader.Close();
                myResponseStream.Close();
     
                return retString;
            }

    　　

    在post的时候有时也用的到cookie，像登录163发邮件时候就需要发送cookie，所以在外部一个cookie属性随时保存 CookieContainer cookie = new CookieContainer();

    ！注意：有时候请求会重定向，但我们就需要从重定向url获取东西，像QQ登录成功后获取sid，但上面的会自动根据重定向地址跳转。我们可以用:
    request.AllowAutoRedirect = false;设置重定向禁用，你就可以从headers的Location属性中获取重定向地址

    Post另一实现：

    post 调用时传参，如：

    string url = "http://www.baidu.com/";
                string result = string.Empty;

                string param = string.Format("WechatOpenID={0}&Content={1}", webchatOpenID, content);
                result = HttpPostData(url, param);

    public string HttpPostData(string url, string param)
            {
                var result = string.Empty;
                //注意提交的编码 这边是需要改变的 这边默认的是Default：系统当前编码
                byte[] postData = Encoding.UTF8.GetBytes(param);

                // 设置提交的相关参数
                HttpWebRequest request = WebRequest.Create(url) as HttpWebRequest;
                Encoding myEncoding = Encoding.UTF8;
                request.Method = "POST";
                request.KeepAlive = false;
                request.AllowAutoRedirect = true;
                request.ContentType = "application/x-www-form-urlencoded";
                request.UserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; .NET CLR 2.0.50727; .NET CLR  3.0.04506.648; .NET CLR 3.5.21022; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)";
                request.ContentLength = postData.Length;

                // 提交请求数据
                System.IO.Stream outputStream = request.GetRequestStream();
                outputStream.Write(postData, 0, postData.Length);
                outputStream.Close();

                HttpWebResponse response;
                Stream responseStream;
                StreamReader reader;
                string srcString;
                response = request.GetResponse() as HttpWebResponse;
                responseStream = response.GetResponseStream();
                reader = new System.IO.StreamReader(responseStream, Encoding.GetEncoding("UTF-8"));
                srcString = reader.ReadToEnd();
                result = srcString;   //返回值赋值
                reader.Close();

                return result;
            }

    Post传输图片等时的代码示例:

    Post多张图片和其他参数时，用此方法进行调用，调用方法如：

    //imgDic是图片接收名称如media,图片本地完整路径或网络完整路径的键值对的集合

    imgDesc是图片信息参数及其他参数的集合，图片信息如media1,media2,media3等，这个图片接收名字是由接收方确定的

    注意：

    FileStream只能用于本地完整路径，如C/xx.jpg等，如果是网路图片则无法使用它。

    推荐使用

    WebClient wc = new WebClient();
                byte[] buffer = wc.DownloadData(filePath);
                memStream.Write(buffer, 0, buffer.Length);

    这种方式，这个类无论是网路图片还是本地图片都可以使用，但路径中要用/，而不是，否则会出现不支持URI的错误。

    if (openIDList != null && openIDList.Any() && imgDesc != null)
                {
                    Dictionary<string, string> imgDic = new Dictionary<string, string>();
                    foreach (var item in imgDesc)
                    {
                        imgDic.Add(item.name, item.path);
                    }

                    NameValueCollection col = new NameValueCollection();
                    col.Add("imgDesc", Newtonsoft.Json.JsonConvert.SerializeObject(imgDesc));
                    col.Add("open_ids", string.Join(",", openIDList));
                    result = HttpPostData(url, 60000, imgDic, col);
                }

    private static string HttpPostData(string url, int timeOut, Dictionary<string, string> imgDic, NameValueCollection stringDict)
            {
                LogEntry entry = new LogEntry("发送图片开始-HttpPostData -- " + stringDict["open_ids"], 1);
                LogStub.Log(entry);

                var firstImg = imgDic.FirstOrDefault();
                string fileKeyName = firstImg.Key;
                string filePath = firstImg.Value;

                string responseContent;
                var memStream = new MemoryStream();
                var webRequest = (HttpWebRequest)WebRequest.Create(url);
                // 边界符
                var boundary = "---------------" + DateTime.Now.Ticks.ToString("x");
                // 边界符
                var beginBoundary = Encoding.ASCII.GetBytes("--" + boundary + " ");
                //var fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read);
               
                // 最后的结束符
                var endBoundary = Encoding.ASCII.GetBytes("--" + boundary + "-- ");

                // 设置属性
                webRequest.Method = "POST";
                webRequest.Timeout = timeOut;
                webRequest.ContentType = "multipart/form-data; boundary=" + boundary;

                // 写入文件
                const string filePartHeader =
                    "Content-Disposition: form-data; name="{0}"; filename="{1}" " +
                     "Content-Type: application/octet-stream ";
                var header = string.Format(filePartHeader, fileKeyName, filePath);
                var headerbytes = Encoding.UTF8.GetBytes(header);

                memStream.Write(beginBoundary, 0, beginBoundary.Length);
                memStream.Write(headerbytes, 0, headerbytes.Length);

                //var buffer = new byte[1024];
                //int bytesRead; // =0

                //while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0)
                //{
                //    memStream.Write(buffer, 0, bytesRead);
                //}

                WebClient wc = new WebClient();
                byte[] buffer = wc.DownloadData(filePath);
                memStream.Write(buffer, 0, buffer.Length);

                //第二章图片
                //memStream.Write(beginBoundary, 0, beginBoundary.Length);


                //var aaa = Encoding.ASCII.GetBytes(" --" + boundary + " ");
                //memStream.Write(aaa, 0, aaa.Length);

                string imgName = string.Empty;
                string imgPath = string.Empty;
                foreach (var img in imgDic.Where(p => p.Key != fileKeyName))
                {
                    imgName = img.Key;
                    imgPath = img.Value;

                    string nxetFileFormat = " --" + boundary + " " + filePartHeader;

                    header = string.Format(nxetFileFormat, imgName, imgPath);
                    headerbytes = Encoding.UTF8.GetBytes(header);

                    memStream.Write(headerbytes, 0, headerbytes.Length);
                    //fileStream = new FileStream(imgPath, FileMode.Open, FileAccess.Read);
                    //while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0)
                    //{
                    //    memStream.Write(buffer, 0, bytesRead);
                    //}

                    buffer = wc.DownloadData(imgPath);
                    memStream.Write(buffer, 0, buffer.Length);
                }

                // 写入字符串的Key
                var stringKeyHeader = " --" + boundary +
                                       " Content-Disposition: form-data; name="{0}"" +
                                       " {1} ";

                foreach (byte[] formitembytes in from string key in stringDict.Keys
                                                 select string.Format(stringKeyHeader, key, stringDict[key])
                                                     into formitem
                                                     select Encoding.UTF8.GetBytes(formitem))
                {
                    memStream.Write(formitembytes, 0, formitembytes.Length);
                }

                // 写入最后的结束边界符
                memStream.Write(endBoundary, 0, endBoundary.Length);

                webRequest.ContentLength = memStream.Length;

                var requestStream = webRequest.GetRequestStream();

                memStream.Position = 0;
                var tempBuffer = new byte[memStream.Length];
                memStream.Read(tempBuffer, 0, tempBuffer.Length);
                memStream.Close();

                requestStream.Write(tempBuffer, 0, tempBuffer.Length);
                requestStream.Close();

                var httpWebResponse = (HttpWebResponse)webRequest.GetResponse();

                using (var httpStreamReader = new StreamReader(httpWebResponse.GetResponseStream(),
                                                                Encoding.GetEncoding("utf-8")))
                {
                    responseContent = httpStreamReader.ReadToEnd();
                }

                fileStream.Close();
                httpWebResponse.Close();
                webRequest.Abort();

                entry = new LogEntry("发送图片结束-HttpPostData -- " + responseContent, 1);
                LogStub.Log(entry);

                return responseContent;
            }

    单行图片调用以下方法时，如：

    NameValueCollection col = new NameValueCollection();
                    //col.Add("media", filePath);
                    col.Add("title", title);
                    col.Add("content", content);
                    col.Add("open_ids", string.Join(",", openIDList));

                    result = HttpPostData(url, 60000, "media", filePath, col);

    filePath是客户端的图片完整路径，

    media是服务端接受图片的参数，这个要看接收端接收图片的参数名，注意此方法是单张图片的post调用

    private static string HttpPostData(string url, int timeOut, string fileKeyName,
                                        string filePath, NameValueCollection stringDict)
            {
                string responseContent;
                var memStream = new MemoryStream();
                var webRequest = (HttpWebRequest)WebRequest.Create(url);
                // 边界符
                var boundary = "---------------" + DateTime.Now.Ticks.ToString("x");
                // 边界符
                var beginBoundary = Encoding.ASCII.GetBytes("--" + boundary + " ");
                var fileStream = new FileStream(filePath, FileMode.Open, FileAccess.Read);
                // 最后的结束符
                var endBoundary = Encoding.ASCII.GetBytes("--" + boundary + "-- ");

                // 设置属性
                webRequest.Method = "POST";
                webRequest.Timeout = timeOut;
                webRequest.ContentType = "multipart/form-data; boundary=" + boundary;

                // 写入文件
                const string filePartHeader =
                    "Content-Disposition: form-data; name="{0}"; filename="{1}" " +
                     "Content-Type: application/octet-stream ";
                var header = string.Format(filePartHeader, fileKeyName, filePath);
                var headerbytes = Encoding.UTF8.GetBytes(header);

                memStream.Write(beginBoundary, 0, beginBoundary.Length);
                memStream.Write(headerbytes, 0, headerbytes.Length);

                var buffer = new byte[1024];
                int bytesRead; // =0

                while ((bytesRead = fileStream.Read(buffer, 0, buffer.Length)) != 0)
                {
                    memStream.Write(buffer, 0, bytesRead);
                }

                // 写入字符串的Key
                var stringKeyHeader = " --" + boundary +
                                       " Content-Disposition: form-data; name="{0}"" +
                                       " {1} ";

                foreach (byte[] formitembytes in from string key in stringDict.Keys
                                                 select string.Format(stringKeyHeader, key, stringDict[key])
                                                     into formitem
                                                     select Encoding.UTF8.GetBytes(formitem))
                {
                    memStream.Write(formitembytes, 0, formitembytes.Length);
                }

                // 写入最后的结束边界符
                memStream.Write(endBoundary, 0, endBoundary.Length);

                webRequest.ContentLength = memStream.Length;

                var requestStream = webRequest.GetRequestStream();

                memStream.Position = 0;
                var tempBuffer = new byte[memStream.Length];
                memStream.Read(tempBuffer, 0, tempBuffer.Length);
                memStream.Close();

                requestStream.Write(tempBuffer, 0, tempBuffer.Length);
                requestStream.Close();

                var httpWebResponse = (HttpWebResponse)webRequest.GetResponse();

                using (var httpStreamReader = new StreamReader(httpWebResponse.GetResponseStream(),
                                                                Encoding.GetEncoding("utf-8")))
                {
                    responseContent = httpStreamReader.ReadToEnd();
                }

                fileStream.Close();
                httpWebResponse.Close();
                webRequest.Abort();

                return responseContent;
            }

     原理简介及简单实现：

    WebRequest request = WebRequest.Create("http://www.baidu.com/");//为指定的 URI 方案初始化新的 System.Net.WebRequest 实例
            request.UseDefaultCredentials = false;//获取或设置一个 System.Boolean 值，该值控制 System.Net.CredentialCache.DefaultCredentials
            WebResponse response = request.GetResponse();//返回对 Internet 请求的响应。
            Stream resStream = response.GetResponseStream();//返回从 Internet 资源返回数据流
            StreamReader sr = new StreamReader(resStream, System.Text.Encoding.Default);//实例华一个流的读写器
            ContentHtml.Text = sr.ReadToEnd();//这就是百度首页的HTML哦 ,字符串形式的流的其余部分（从当前位置到末尾）。如果当前位置位于流的末尾，则返回空字符串 ("")
            resStream.Close();//关闭当前流并释放与之关联的所有资源
            sr.Close(); //关闭 System.IO.StreamReader 对象和基础流，并释放与读取器关联的所有系统资源

    HttpWebRequest 和 HttpWebResponse 的应用

    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(addr);
    // Downloads the XML file from the specified server.
    HttpWebResponse response = (HttpWebResponse)request.GetResponse();
    System.IO.StreamReader sr     = new StreamReader(response.GetResponseStream(), System.Text.Encoding.GetEncoding("gb2312"));
    Console.Write(sr.ReadToEnd());
    sr.Close();
    response.Close();


    1.获取http地址上的图片
    http://www.cnblogs.com/fooo/archive/2007/06/28/798335.html
    HttpWebResponse resp;
            HttpWebRequest req     = (HttpWebRequest)HttpWebRequest.Create("http://www.csdn.net/Images/logo_csdn.gif");
            req.Timeout     = 150000;
            resp     = (HttpWebResponse)req.GetResponse();
            System.Drawing.Image img;
            img     = new System.Drawing.Bitmap(resp.GetResponseStream());

    2.

    HttpWebRequest&HttpWebResponse Headers

    介绍

    这里简要介绍如何使用HttpWebRequest&HttpWebResponse两个对象与HTTP服务器进行直接交互的过程.HttpWebRequest类对WebRequest中定义的属性和方法提供支持,在使用HttpWebRequest对象向HTTP服务器发起请求时请不要使用HttpWebRequest对象的构造函数,而应该使用WebRequest.Create()方法来初始化新的HttpWebRequest对象.如果统一资源标识符方案是"http://"或"https://"时,Create()则返回HttpWebResponse对象.

    代码

    首先,我们需要创建一个新的HttpWebRequest对象,代码如下:

    HttpWebRequest myrequest = (HttpWebRequest)WebRequest.Create(new Uri("urlstring"));

    注意:上文中已经提到过不要使用HttpWebRequest的构造函数来创建对象;使用WebRequest.Create()方法初始化HttpWebRequest对象时应该对其进行类型转换.

    接下来可以对新初始化的对象进行简单操作,比如可以设置它的标头属性,
    下表列出了由属性或方法设置或由系统设置的标头:


    标头

    设置方法

    Accept                 由Accept属性设置                
    Connection                     由Connection属性和KeepAlive属性设置                    
    Content-Length                         由ContentLength属性设置                        
    Content-Type                             由ContentType属性设置                            
    Expect                                 由Expect属性设置                                
    Date                                     由系统设置为当前日期                                    
    Host                                         由系统设置为当前主机信息                                        
    If-Modified-Since                                             由IfModifiedSince属性设置                                            
    Range                                                 由Range属性设置                                                
    Transfer-Encoding                                                     由TransferEncoding属性设置                                                    
    Referer                                                         由Referer属性设置                                                        
    User-Agent                                                            

    由UserAgent属性设置

    注意:HttpWebRequest自动注册.使用以"http://"或"https://"开头的URL之前,不需要调用RegisterPrefix方法来注册                                                

    System.Net.HttpWebRequest选自:
    MSDN:ms-help://MS.MSDNQTR.v80.chs/MS.MSDN.v80/MS.NETDEVFX.v20.chs/cpref10/html/T_System_Net_HttpWebRequest.htm                                                    

    在完成对服务器的请求之后,我们需要获取从服务器中返回的信息,正如前面提到过的,使用HttpWebResponse类,具体做法参照如下代码:                                                

    HttpWebResponse myresponse = (HttpWebResponse)myrequest.GetResponse();                                                

    同样这里我们需要使用HttpWebResponse进行类型转换.到这里,我们已经成功的获得服务器返回的信息,一个myresponse对象,我们可以利用它来获得更多详细的信息,比如从服务器返回的Headers标头,还有其他的有用信息.而在此我们只给您列出如何获得来自服务器响应的Headers标头信息.我们的具体方法是这样的:                                                

            #region GetHeaders                                                

            public static WebHeaderCollection GetHeaders(Uri uri)                                                

            {                                                

                HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);                                                

                // 省略部分代码......                                                

                HttpWebResponse response = (HttpWebResponse)request.GetResponse();                                                

                // 省略部分代码......                                                

                return response.Headers;                                                

            }                                                

            #endregion                                                

    下面就是提供的main()函数:                                                

            // The app entry point                                                

            public static void Main(string[] args)                                                

            {                                                

                WebHeaderCollection headers = GetHeaders(new Uri("http://www.listim.net"));                                                

                string[] headkeys = headers.AllKeys;                                                

                Console.WriteLine("{0,-30}{1}", "Name", "Value");                                                

                Console.WriteLine("--------------------------------");                                                

                foreach (string s in headkeys)                                                

                {                                                

                    Console.WriteLine("{0,-30}{1}", s, headers[s]);                                                

                }                                                

            }

    另一种实现方式：

    /// <summary>
            /// Post data到url
            /// </summary>
            /// <param name="data">要post的数据</param>
            /// <param name="url">目标url</param>
            /// <returns>服务器响应</returns>
            static string PostDataToUrl(string data, string url)
            {
                Encoding encoding = Encoding.GetEncoding(sRequestEncoding);
                byte[] bytesToPost = encoding.GetBytes(data);
                return PostDataToUrl(bytesToPost, url);
            }

            /// <summary>
            /// Post data到url
            /// </summary>
            /// <param name="data">要post的数据</param>
            /// <param name="url">目标url</param>
            /// <returns>服务器响应</returns>
            static string PostDataToUrl(byte[] data, string url)
            {
                #region 创建httpWebRequest对象
                WebRequest webRequest = WebRequest.Create(url);
                HttpWebRequest httpRequest = webRequest as HttpWebRequest;
                if (httpRequest == null)
                {
                    throw new ApplicationException(
                    string.Format("Invalid url string: {0}", url)
                    );
                }
                #endregion

                #region 填充httpWebRequest的基本信息
                httpRequest.UserAgent = sUserAgent;
                httpRequest.ContentType = sContentType;
                httpRequest.Method = "POST";
                #endregion

                #region 填充要post的内容
                httpRequest.ContentLength = data.Length;
                Stream requestStream = httpRequest.GetRequestStream();
                requestStream.Write(data, 0, data.Length);
                requestStream.Close();
                #endregion


                #region 发送post请求到服务器并读取服务器返回信息
                Stream responseStream;
                try
                {
                    responseStream = httpRequest.GetResponse().GetResponseStream();
                }
                catch (Exception e)
                {
                    // log error
                    Console.WriteLine(
                    string.Format("POST操作发生异常：{0}", e.Message)
                    );
                    throw e;
                }
                #endregion

                #region 读取服务器返回信息
                string stringResponse = string.Empty;
                using (StreamReader responseReader =
                new StreamReader(responseStream, Encoding.GetEncoding(sResponseEncoding)))
                {
                    stringResponse = responseReader.ReadToEnd();
                }
                responseStream.Close();
                #endregion
                return stringResponse;
            }

    调用时：

    string param = string.Format("time={0}&oid={1}&order={2}&name={3}&area={4}&point={5}&amount={6}&return={7}&hash={8}&version={9}", Time, Oid, OrderID, LoginName, Area, Point, Amount, ReturnUrl, HashMoli, Version);

    string result = PostDataToUrl(param, PostUrl);

    还有一种实现的例子：

    使用httpwebrequest Post数据到网站

    怎样通过HttpWebRequest 发送 POST 请求到一个网页服务器？例如编写个程序实现自动用户登录，自动提交表单数据到网站等。
    假如某个页面有个如下的表单（Form）：
    <form name="form1" action="http://www.here.com/login.asp" method="post">
      <input type="text" name="userid" value="">
      <input type="password" name="password" value="">
    < /form>
        
    从表单可看到表单有两个表单域，一个是userid另一个是password，所以以POST形式提交的数据应该包含有这两项。
    其中POST的数据格式为：
    表单域名称1=值1&表单域名称2=值2&表单域名称3=值3……
    要注意的是“值”必须是经过HTMLEncode的，即不能包含“<>=&”这些符号。

    本例子要提交的数据应该是：
    userid=value1&password=value2

    用C#写提交程序：

      string strId = "guest";
      string strPassword= "123456";

      ASCIIEncoding encoding=new ASCIIEncoding();
      string postData="userid="+strId;
      postData += ("&password="+strPassword);

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

      // Prepare web request...
      HttpWebRequest myRequest =
       (HttpWebRequest)WebRequest.Create("http://www.here.com/login.asp");

      myRequest.Method = "POST";
      myRequest.ContentType="application/x-www-form-urlencoded";
      myRequest.ContentLength = data.Length;
      Stream newStream=myRequest.GetRequestStream();

      // Send the data.
      newStream.Write(data,0,data.Length);
      newStream.Close();

      // Get response
      HttpWebResponse myResponse=(HttpWebResponse)myRequest.GetResponse();
      StreamReader reader = new StreamReader(response.GetResponseStream(),Encoding.Default);
      string content = reader.ReadToEnd();
      Console.WriteLine(content);
     
     
     
  • 相关阅读:
    简单的多重背包
    完美子图
    活动投票
    人品问题
    售票系统
    最短路径
    优美值
    前端-常用函数记录-持续更新
    前端-单点登录中cookie中domain的思考
    大白话说GIT常用操作，常用指令git操作大全
  • 原文地址：https://www.cnblogs.com/itjeff/p/4022220.html
Copyright © 2011-2022 走看看