javascript - FormData in IE8/9 -

i have implemented script uploading files ajax, works perfect in other browsers except explorer, noticed formdata not supported ie9 , less, there alternatives formdata in ie, , want use clean javascript

    function doobjuploadexplorer(url, lnk_id, file, progress, success, content, frm, div_dlg, start_func){     var file_input = null,       frm_data = new formdata(),       req;      try {         //firefox, chrome, safari etc         req = new xmlhttprequest();     }      catch (e) {         // internet explorer browsers         req = new activexobject("microsoft.xmlhttp");     }   if (document.getelementbyid(file)) {     file_input = document.getelementbyid(file);      (var = 0; < file_input.files.length; ++i) {         frm_data.append(file, file_input.files[i]);     } }  req.upload.addeventlistener('progress', function(e) {  //event called while upload in progress     if (progress !== undefined             && e.lengthcomputable) {         $('#' + progress).html('<font>uploading... ' + math.round((e.loaded / e.total) * 100) + '%</font>');     } });  req.upload.addeventlistener('load', function(e) {  //event called when upload completed     $('#' + progress).html('<font>retrieving updated data...</font>'); });  req.upload.addeventlistener('error', function(e) {  //event called when error returned server     alert('an error has occurred...'); });  req.addeventlistener('readystatechange', function(e) {             if (this.readystate === 4) {         if (this.status === 200) {             if (content !== undefined) {                 $('#' + content).html(this.response);             }              if (success !== undefined) {                 showchkmark(success);             }         } else {             console.log('server replied http status: ' + this.status);         }           if (progress !== undefined) {             $('#' + progress).hide();         }          if (div_dlg !== undefined) {             $('#' + div_dlg).dialog('close');         }          $('#' + file)         .attr('disabled', false)         .val('');     } });  if (progress !== undefined) {     $('#' + progress).show(); }  $('#' + file).attr('disabled', true); url += (         url.indexof('?') === -1         ? '?'         : '&'     ); url += 'lnk_id=' + lnk_id + '&file=' + file; req.open('post', url); req.setrequestheader('cache-control', 'no-cache');  if (start_func !== undefined) {     start_func.apply();     settimeout(function() {         req.send(frm_data);     }, 500); } else {     req.send(frm_data); }} 

formdata in ie supported ie10, after doing research best solution (my opinion) using ajaxform: http://malsup.com/jquery/form/ works perfect in ie8/9, not sure ie7