c# - How upload image to server with multipart form data -

i want emulate request

this logs sniffer

 -----------------------------708299735697 content-disposition: form-data; name="_file"  1.jpg -----------------------------708299735697 content-disposition: form-data; name="file"; filename="blob" content-type: image/png  ‰png ............ 

that code on csharp.

var taimalda = datetime.now.ticks;   var boundary = "------------------------" + taimalda ; var newline = environment.newline; var propformat = "--" + boundary + newline +                  "content-disposition: form-data; name=\"{0}\"" + newline + newline +                  "{1}" + newline; var fileheaderformat = "--" + boundary + newline +                        "content-disposition: form-data; name=\"{0}\"; filename=\"{1}\"" +                            newline + "content-type: image/png";  var req = (httpwebrequest)httpwebrequest.create("http://xxx.ru/new_style/flash_uploader/upload.php?fileapi"+taimalda); req.cookiecontainer = s; //  system.net.servicepointmanager.expect100continue = false; req.referer = "http://www.xxx.ru/user/setting/set_info"; // add referer  req.useragent = "mozilla/5.0 (windows nt 6.1; wow64; rv:2.0) gecko/20100101 firefox/4.0";   // add useragent req.method = webrequestmethods.http.post;  // post request req.contenttype = "multipart/form-data; boundary=" + boundary;  using (var reqstream = req.getrequeststream()) {     var reqwriter = new streamwriter(reqstream);     var tmp = string.format(propformat, "_file", "1.jpg");     reqwriter.write(tmp);     tmp = string.format(fileheaderformat, "file", "blob");     reqwriter.write(tmp);     reqwriter.flush(); } var res = req.getresponse(); using (var resstream = res.getresponsestream()) {      var reader = new streamreader(resstream);      var ext = reader.readtoend(); } 

but code sent headers without file(1.jpg)

     -----------------635031060420469298     content-disposition: form-data; name="_file"      1.jpg     --------------------------635031060420469298     content-disposition: form-data; name="file"; filename="blob"     content-type: image/png 

i don't see anywhere reading bytes of 1.jpg file , writing request stream.