C # Impersonation submits a form with file upload

------Webkitformboundary8gsfyexbioo5oyaacontent-disposition:form-data; Name= "username" admin------webkitformboundary8gsfyexbioo5oyaacontent-disposition:form-data; Name= "Submit" login------webkitformboundary8gsfyexbioo5oyaacontent-disposition:form-data; Name= "Max_file_size"; Filename= "2aêo1üàí.txt" content-type:text/plain//unrecognized file format, such as RAR for Content-type:application/octet-stream. PDF is content-type:application/pdf------webkitformboundary8gsfyexbioo5oyaa--

The request data stream format is:------fixed boundary character//1, the boundary character is consistent with Content-type:multipart/form-data in the request header; boundary=----Webkitformboundaryxxbqdgnaymzzuaxzcontent-disposition:form-data; Name= "username"//2, content description and content name//2.1, if uploading the file you need to fill in the file type Content-type:text/plain//3, empty line//4, string or file binary//If there are other data to be submitted Repeat 1-4------fixed boundary characters//5, end of boundary should be added at the end

C # analog upload file code

Public postfile (String action,string file)  {             //1, data boundaries              string boundary =  "---------------------------"  + datetime.now.ticks.tostring ("X");             //2, creating HttpWebRequest requests              HttpWebRequest myRequest =  WebRequest.Create (Action)  as HttpWebRequest;             myRequest.Method =  "POST";             //3, set request contenttype  and   boundary characters (the boundary character must be the same as the boundary character of the request data body   Otherwise the server cannot resolve)              myRequest.ContentType =  "Multipart/form-data; Boundary= " + boundary;&nbSP;           //4, adding file Data description information              stringbuilder sb = new stringbuilder ();             SB. Append ("--"  + boundary);             sb. Append ("\ r \ n");            //name  for   Upload the file INPUT NAME            SB. Append ("Content-disposition: form-data; name= ' max_file_size ';  filename=\" " + file  +  "\" ");             sb. Append ("\ r \ n");             sb. Append ("Content-type: application/octet-stream");  //here is a simulated file type, in which case the browser will actually determine this type based on the local file suffix name   & NBSP;         SB. Append ("\r\n\r\n");            encoding  Encoding = encoding.getencoding ("GBK");  //here encoding must be encoded with the Web page   Otherwise cause the Chinese path or file name garbled   But the contents of the file will not be garbled              byte[] form_data = encoding. GetBytes (sb.) ToString ());             //5, footer Data              byte[] foot_data = encoding. GetBytes ("\r\n--"  + boundary +  "--\r\n");                         //6, read files              using  (filestream filestream  = new filestream (file, filemode.open, fileaccesS.read))             {                 stringbuilder sb2 = new  stringbuilder ();                 SB2. Append ("--"  + boundary);                 SB2. Append ("\ r \ n");                 SB2. Append ("content-disposition: form-data; name= ' username '; \ r \ n");  //sent content title                  SB2. Append ("\ r \ n");                 SB2. Append ("Chinese name");  //send content              & nbsp;   sb2. Append ("\ r \ n")  //each set of data ends with a newline character to be added                  SB2. Append ("--"  + boundary);                 SB2. Append ("\ r \ n");                 SB2. Append ("Content-disposition: form-data; name= ' pwd '; \ r \ n");                 SB2. Append ("\ r \ n");                 SB2. Append ("QADSFDSFA");                 SB2. Append ("\ r \ n");                 byte[] data = encoding. GetBytes (SB2. ToString ());                //6, set upload data length to header  +  file  +  Footer Length                  myrequest.contentlength = form_data. Length + foot_data. Length + filestream.length + data. LENGTH;                //7, Get the requested data stream                 stream  requeststream = myrequest.getrequeststream ();                 //8.1, writing character information data to request flow                  requeststream.write (Data, 0, data. Length);                 //8.2, Write the file information dataIncoming Request Flow                  requestStream.Write (Form_data, 0, form_data. Length);                 //9, Loop read file stream   Write request flow                  byte[] buffer = new byte[checked (UINT) math.min (4096,  (int) fileStream.Length))] ;                int  bytesread = 0;                 while  (Bytesread = filestream.read (Buffer, 0, buffer. Length))  != 0)                  {               &nbSp;    requeststream.write (Buffer, 0, bytesread);                 }                                  //10, writes end boundary data to the request stream                  requeststream.write (Foot_data, 0, foot_data. Length);            }             //11, initiating a request              httpwebresponse myresponse = myrequest.getresponse ()  as  HTTPWEBRESPONSE;            //12, read request return Data flow               streamreader sr = new streamreader (MyResponse.GetResponseStream () ,  encoding);             string json  = SR. ReadToEnd (). Trim ();             clipboard.settext (JSON);             messagebox.show (JSON);                     }

C # Impersonation submits a form with file upload