c# - File uploads to asp.net web api using pure javascript via ajax -

i trying file uploads through ajax web api. server side codes prove working cause have managed post files using debugging fiddler , works fine. failing write successful javascript code able upload.

below html code:

function sendimage() {    var data = new formdata();    var file = document.getelementbyid('upload').files[0];      data.append("image",file);    if (window.xmlhttprequest) {// code ie7+, firefox, chrome, opera, safari      xmlhttp_br=new xmlhttprequest();    }    else {// code ie6, ie5      xmlhttp_br=new activexobject("microsoft.xmlhttp");    }    xmlhttp_br.onreadystatechange = function () {      if (xmlhttp_br.readystate == 4 ) {        var data = xmlhttp_br.responsetext;        alert(xmlhttp_br.status+" "+data);        var file = json.parse(data);      }    } 	      xmlhttp_br.open("post","http://localhost:59103/"+"api/upload/testupload",true);    xmlhttp_br.setrequestheader("content-type","multipart/form-data");    xmlhttp_br.setrequestheader("filename", file.name);    xmlhttp_br.send(data);  }

<input name="uploadedimage" id="upload" type="file"  accept="image/*">  <button onclick="sendimage()"> upload image </button>  <img id ="image">

my c# server side code follows

public async task<ihttpactionresult> postfile() {   httprequestmessage request = this.request;   if (!request.content.ismimemultipartcontent())   {     throw new httpresponseexception(httpstatuscode.unsupportedmediatype);   }    var provider = new multipartmemorystreamprovider();   await request.content.readasmultipartasync(provider);   stream img = null;   string filename ="";   foreach (var file in provider.contents)   {     filename = file.headers.contentdisposition.filename.trim('\"');     img = await file.readasstreamasync();     //do whatever want filename , binaray data.   }    bool status = uploadfiletos3(filename, img, "edu-media");    if (status)   {     return ok();   }   else   {     return statuscode(httpstatuscode.expectationfailed);   } } 

note saving files aws s3 buckets , don't want jquery, pure javascript.