Select multiple classes with attr. with jQuery

Question

I have a function that I use for an interactive map, where I hover an element to show a specific region based on class that matches a country suffix. Im trying to figure out how to select multiple classes to show multiple regions.

Code:

var mapObj = jQuery('#vmap').data('mapObject');

            jQuery('#countries').on('mouseover mouseout', 'a:first-child', function (event) {
                // event.preventDefault();
                var elem = event.target,
                    evtype = event.type;

                if (evtype === 'mouseover') {
                    mapObj.select(jQuery(elem).attr('class'));
                } else {
                    mapObj.deselect(jQuery(elem).attr('class'));
                };
            });

};

<ul id="countries">
  <li><a class="SE" href="">Sweden</a></li>
  <li><a class="DK" href="">Denmark</a></li>
</ul>

I might going this the wrong way, but I would like to target mutiple regions by using several classes:

<li><a class="SE DK" href="">Sweden and Denmark</a></li>

This of course doesn't work but illustrates what I want to do. whats the best approach here?

Example:

       jQuery('#vmap').vectorMap({
            map: 'world_en',
onLabelShow: function (event, label, code) {
        
                if (code == 'se') {
                var countryName = label[0].innerHTML;
          var html = ['<span class="tooltip-up arrow-down-center">',
           countryName,
': 50% of production',
          '</span>'
          ].join("");
          label[0].innerHTML = html;
                }
        },
            backgroundColor: '#fff',
            enableZoom: false,
            color: '#ffffff',
            hoverOpacity: 0.7,
            selectedColor: '#666666',
            showTooltip: true,
            values: sample_data,
            scaleColors: ['#C8EEFF', '#006491'],
            normalizeFunction: 'polynomial',                           
            pinMode: 'content',
            regionsSelectableOne: false,
                regionsSelectable: false,
                series: {
                regions: [{
                  scale: ['#C8EEFF', '#0071A4'],
                  normalizeFunction: 'polynomial'
               }]
             }
        });
 var mapObj = jQuery('#vmap').data('mapObject');

            jQuery('#countries').on('mouseover mouseout', 'a:first-child', function (event) {
                // event.preventDefault();
                var elem = event.target,
                    evtype = event.type;

                if (evtype === 'mouseover') {
                    mapObj.select(jQuery(elem).attr('class'));
                } else {
                    mapObj.deselect(jQuery(elem).attr('class'));
                };
            });

<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<link href="https://www.10bestdesign.com/jqvmap/assets/jqvmaps/jqvmap.css" media="screen" rel="stylesheet" type="text/css">
<script src="https://www.10bestdesign.com/jqvmap/assets/jqvmaps/jquery.vmap.js"></script>
        <script src="https://www.10bestdesign.com/jqvmap/assets/jqvmaps/maps/jquery.vmap.world.js"></script>
        <script src="https://www.10bestdesign.com/jqvmap/assets/jqvmaps/jquery.vmap.sampledata.js"></script>

  
<div id="vmap" style="width: 800px; height: 400px;"></div>

<ul id="countries">
  <li><a class="SE" href="">Sweden</a></li>
  <li><a class="DK" href="">Denmark</a></li>
   <li><a class="SE DK" href="">Sweden and Denmark</a></li>
</ul>

Answer 1

You can modify your select/deselect function to accept array of classes, or instead loop the classes and invoke select/deselect for each class name:

var mapObj = jQuery('#vmap').data('mapObject');

        
jQuery('#countries').on('mouseover mouseout', 'a:first-child', function (event) {
  var elem = event.target;
  var countryCodes = jQuery(elem).attr('class').split(/\s+/);

  evtype = event.type;

  if (evtype === 'mouseover') {
    jQuery.each(countryCodes, function(index, code) {
       mapObj.select(code);
    });
  } else {
    jQuery.each(countryCodes, function(index, code) {
      if (mapObj.isSelected(code)) {
        mapObj.deselect(code);
      } else {
        mapObj.select(code);
        mapObj.deselect(code);
      }
    });
  };
});