<script type="text/javascript">
function preventDefault(e) {
  e = e || window.event;
  if (e.preventDefault)
      e.preventDefault();
  e.returnValue = false;
}

function theMouseWheel(e) {
  preventDefault(e);
}

function disable_scroll() {
  if (window.addEventListener) {
      window.addEventListener('DOMMouseScroll', theMouseWheel, false);
  }
  window.onmousewheel = document.onmousewheel = theMouseWheel;
}

function enable_scroll() {
    if (window.removeEventListener) {
        window.removeEventListener('DOMMouseScroll', theMouseWheel, false);
    }
    window.onmousewheel = document.onmousewheel = null;
}

$(function () {
  $(".modal").on('shown.bs.modal', function () {disable_scroll();});
  $(".modal").on('hidden.bs.modal', function () {enable_scroll();});
});