Super simple jQuery file drop plugin

jquery.filedropper.js

/**
 * Very simple file drop plugin
 * @author Arjan Haverkamp - webgear.nl
 * @date 2019-01-21
 */
(function($) {
   $.fn.FileDropper = function(options) {

      var settings = $.extend({
         // These are the defaults.
         overSelector: this,
         overClass: 'over',
         multiple: false, // Whether or not to accept multiple files
         onDrop: null,
         skipClassName: null // Don't do anything when my selector contains this class name
      }, options);

      var dragCounter = 0, disabled = false;

      return this.each(function() {
         var $this = $(this);

         $this
         .on('dragenter', function(e) {
            if (settings.skipClassName) {
               disabled = $this.hasClass(settings.skipClassName);
               if (disabled) { return; }
            }

            if (++dragCounter == 1) {
               //$this.addClass(settings.overClass);
               $(settings.overSelector).addClass(settings.overClass);
            }
         })
         .on('dragover', function(e) {
            if (disabled) { return; }

            e.preventDefault();
            e.originalEvent.dataTransfer.dropEffect = 'copy';
         })
         .on('dragleave', function(e) {
            if (disabled) { return; }

            if (--dragCounter == 0) {
               //$this.removeClass(settings.overClass);
               $(settings.overSelector).removeClass(settings.overClass);
            }
         })
         .on('drop', function(e) {
            if (disabled) { return; }
            e.stopPropagation();
            e.preventDefault();
            //$this.removeClass(settings.overClass);
            $(settings.overSelector).removeClass(settings.overClass);
            dragCounter = 0;
            var files = e.originalEvent.dataTransfer.files;
            if (files.length == 0 || (!settings.multiple && files.length > 1)) {
               return;
            }
            settings.onDrop && settings.onDrop(!settings.multiple ? files[0] : files);
         })
      });
   };
}(jQuery));

Serving suggestion:

$('body').FileDropper({
   skipClassName: 'modal-open',
   onDrop: function(file) {
      if (/\.(jpg|jpeg|png|gif)$/.test(file.name)) {
         loadImage(file);
      }
   }
});

function loadImage(file) {
   var reader = new FileReader();
   reader.onload = function() {
      console.log(this.result);
   }
   reader.readAsDataURL(file);
}