var tag = 0;
 function addFile(model,id){
   var parent = document.getElementById(id);   
   parent.appendChild(createFileField(model , id)); 
   setFlag(); 
}


 function createFileField(model,id){
   tag +=1;
   var div = document.createElement('div');    
   var file = document.createElement('input');
   var del = document.createElement('a');
   div.setAttribute("id",model+'_'+tag);
   file.setAttribute("id",model+tag+'_'+model);
   file.setAttribute("name",model+tag+'['+model+']');
   file.setAttribute("size",30);
   file.setAttribute("type",'file');  
   var href = "javascript:removeFile('"+id+"',"+tag+",'"+model+"')";
   del.setAttribute("href" ,href);
   del.innerHTML="Delete";   
   div.appendChild(file); 
   div.appendChild(del);
   return div;
}

 function removeFile(parent,tag,model){
   var remove = document.getElementById(model+'_'+tag);
   var parent = document.getElementById(parent);
   parent.removeChild(remove);
   removeFlag('fileFlag',tag);
}
 function setFlag(){
   var flags =document.getElementById('fileFlag');
   flags.value+=":"+tag;  
}
 function removeFlag(id,tag){
   var flags =document.getElementById(id);
   var value="";   
   array=flags.value.split(":")
   for(var i=1;i<array.length;i++){
      if(parseInt(array[i])!=tag){
	  value+=":"+array[i];
      }
   }	  
   flags.value = value;
}