HTML5 dragOut jQuery Plugin

jQuery.dragOutLink.js

(function($) {
  $.event.props.push("dragstart");
  $.fn.dragOutLink = function() {
    return this.each(function() {
      var $this = $(this),
          href = $this.attr("href"),
          fileName = href.match(/[-_\w]+[.][\w]+$/i)[0];
      if (!!window.FileReader) {
         var header = $.ajax({
          type:     "HEAD",
          url:      $this.attr("href"),
          success:  function(data) {
            $this.attr("data-downloadurl", header.getResponseHeader("Content-Type") + ":" + fileName + ":" + href);
          }
        });
        $this.bind("dragstart",function(){
          if (this.dataset) {
            event.dataTransfer.setData('DownloadURL', this.dataset.downloadurl);
          }
        });
      }
    });
  }
})(jQuery);