var upload_limit = 10;
var upload_slots = 1;

function UpdateUploadSlots()
{
  upload_slots++;

  //  if (upload_slots <= upload_limit) {
  if (upload_slots <= upload_limit) {
    new_slot = document.createElement("p");
    new_slot.innerHTML = "<input  class='file' type='file' name='image_upload[]' size='70' />";
    document.getElementById("uploadBoxes").appendChild(new_slot);
  }

  if (upload_slots >= upload_limit) {
    document.getElementById("addUploadBox").innerHTML = '';
  }
}