function loadjscssfile(filename, filetype){
 if (filetype=="js"){ //if filename is a external JavaScript file
  var fileref=document.createElement('script')
  fileref.setAttribute("type","text/javascript");
  fileref.setAttribute("src", filename);
 }
 else if (filetype=="css"){ //if filename is an external CSS file
  var fileref=document.createElement("link")
  fileref.setAttribute("rel", "stylesheet");
  fileref.setAttribute("type", "text/css");
  fileref.setAttribute("href", filename);
 }
 if (typeof fileref!="undefined")
  document.getElementsByTagName("head")[0].appendChild(fileref)
}

var filesadded="" //list of files already added

function checkloadjscssfile(filename, filetype){
 if (filesadded.indexOf("["+filename+"]")==-1){
  loadjscssfile(filename, filetype)
  filesadded+="["+filename+"]" //add to list of files already added, in the form of "[filename1],[filename2],etc"
 }
 
 
}