利用HttpWebRequest模拟表单提交

  1 using system;
  2 using system.collections.specialized;
  3 using system.io;
  4 using system.net;
  5 using system.text;
  6 
  7 namespace allyn.common
  8 {
  9     public class httphelper
 10     {
 11         /// <summary>
 12         /// 获取指定路径数据
 13         /// </summary>
 14         /// <param name="requesturi">提交路径</param>
 15         /// <param name="cookie">cookie容器对象</param>
 16         /// <returns>字符串结果</returns>
 17         public static string getform(string requesturi, cookiecontainer cookie)
 18         {
 19             httpwebrequest request = webrequest.createhttp(requesturi);
 20             request.method = "get";
 21             request.cookiecontainer = cookie;
 22             request.contentlength = 0;
 23 
 24             webresponse response = request.getresponse();
 25             streamreader reader = new streamreader(response.getresponsestream(), encoding.utf8);
 26             return reader.readtoend();
 27         }
 28 
 29         /// <summary>
 30         /// 默认表单提交
 31         /// </summary>
 32         /// <param name="requesturi">提交路径</param>
 33         /// <param name="postdata">提交数据</param>
 34         /// <param name="cookie">cookie容器对象</param>
 35         /// <returns>字符串结果</returns>
 36         public static string postform(string requesturi, namevaluecollection postdata, cookiecontainer cookie)
 37         {
 38             httpwebrequest request = webrequest.createhttp(requesturi);
 39             request.method = "post";
 40             request.contenttype = "application/x-www-form-urlencoded";
 41             request.cookiecontainer = cookie;
 42 
 43             stringbuilder stringbuilder = new stringbuilder();
 44             foreach (string key in postdata.keys)
 45             {
 46                 stringbuilder.appendformat("&{0}={1}", key, postdata.get(key));
 47             }
 48             byte[] buffer = encoding.utf8.getbytes(stringbuilder.tostring().trim('&'));
 49             stream requeststream = request.getrequeststream();
 50             requeststream.write(buffer, 0, buffer.length);
 51             requeststream.close();
 52 
 53             webresponse response = request.getresponse();
 54             streamreader reader = new streamreader(response.getresponsestream(), encoding.utf8);
 55             return reader.readtoend();
 56         }
 57 
 58         /// <summary>
 59         /// 多部件表单提交
 60         /// </summary>
 61         /// <param name="requesturi">提交路径</param>
 62         /// <param name="postdata">提交数据.注:如果是文件路径,代表是文件.</param>
 63         /// <param name="cookie">cookie容器对象</param>
 64         /// <returns>字符串结果</returns>
 65         public static string postformmultipart(string requesturi, namevaluecollection postdata, cookiecontainer cookie)
 66         {
 67             string boundary = string.format("-----{0}", datetime.now.ticks.tostring("x"));
 68             httpwebrequest webrequest = webrequest.createhttp(requesturi);
 69             webrequest.cookiecontainer = cookie;
 70             webrequest.timeout = 120000;
 71             webrequest.method = "post";
 72             webrequest.contenttype = string.format("multipart/form-data; boundary={0}", boundary);
 73 
 74             stream requeststream = webrequest.getrequeststream();
 75             foreach (string key in postdata.keys)
 76             {
 77                 stringbuilder strbuilder = new stringbuilder();
 78                 strbuilder.appendformat("--{0}", boundary);
 79                 strbuilder.appendformat("\r\ncontent-disposition: form-data; name=\"{0}\"", key);
 80                 if (file.exists(postdata.get(key)))
 81                 {
 82                     strbuilder.appendformat(";filename=\"{0}\"\r\ncontent-type: multipart/form-data\r\n\r\n", path.getfilename(postdata.get(key)));
 83                     byte[] buffer = encoding.utf8.getbytes(strbuilder.tostring());
 84                     requeststream.write(buffer, 0, buffer.length);
 85                     //获取图片流
 86                     filestream filestream = new filestream(postdata.get(key), filemode.open, fileaccess.read);
 87                     binaryreader binaryreader = new binaryreader(filestream);
 88                     byte[] filebuffer = binaryreader.readbytes((int)filestream.length);
 89                     binaryreader.close();
 90                     filestream.close();
 91                     requeststream.write(filebuffer, 0, filebuffer.length);
 92                 }
 93                 else
 94                 {
 95                     strbuilder.appendformat("\r\n\r\n{0}\r\n", postdata.get(key));
 96                     byte[] buff = encoding.utf8.getbytes(strbuilder.tostring());
 97                     requeststream.write(buff, 0, buff.length);
 98                 }
 99             }
100 
101             byte[] boundarybuffer = encoding.utf8.getbytes(string.format("\r\n--{0}\r\n", boundary));
102             requeststream.write(boundarybuffer, 0, boundarybuffer.length);
103             requeststream.close();
104 
105             webresponse response = webrequest.getresponse();
106             streamreader reader = new streamreader(response.getresponsestream(), encoding.utf8);
107             return reader.readtoend();
108         }
109     }
110 }