Simple Javascript File Adder

Bored, made this simple file adder, actually you can add text fields also, I should add options into it for it to be able to also remove the created input fields.

files={elms:[],count:0,add:function(id,name,type,max,prefix){if(max&&((files.count+1)>max))return;var elm,cont,label;elm=cont=label=null;cont=document.getElementById(id);type=(type) ? type : "file";if(!cont) return alert("addboxes.js: Container for adding elements does not exists");name=(!name) ? "files" : name;elm=document.createElement("input");elm.setAttribute("name",name+"[]");elm.setAttribute("type",type);label=document.createElement("label");label.setAttribute("class","autoadd");if(prefix) label.appendChild(document.createTextNode(prefix+' '+(files.count+1)));label.appendChild(elm);cont.appendChild(label);files.elms[files.elms.length]=elm;files.count++;}}/*Example Usage: <a href="javascript:files.add('emails','reviews','text',4,'Review #');">[+]Add Email</a> <div id="emails"></div>*/