collector

    <!--- HTML -->
    <input type="text" name="class_div[]" class="form-control class_div" value="multi"/>
    <input type="text" name="class_div[]" class="form-control class_div" value="input"/>
    <input type="text" name="class_div[]" class="form-control class_div" value="data"/>
    <input type="text" name="class_div[]" class="form-control class_div" value="collector"/>
    <!--- HTML -->
    <!--- JS -->
    var data = document.getElementsByClassName('class_div'),
      join_data = [].map.call(data , function (_d) {
        return _d.value;
    }).join(',');
    <!--- JS -->