Please what is the proper synthax?

Please what is the proper synthax?

hello,

I am trying to parse a value into a plugin, but it does not work. an alert(myborderimage); shows that I am getting the value, but I cannot parse it to jQuery

  1.         $(document).ready(function(){
  2. var myborderimage = $("#myborderimage").val();
  3. $('#myborder').borderImage('url("borders/+myborderimage+") 30% 35% 40% 30%');
  4. });
thank you