How to count the html array elements

To count the html elements, it's better to set and use the className attribute.
     Ex:
      input type="text" class="clsUser" name="user[1][]"
      input type="text" class="clsUser" name="user[1][]"

      Then in the javascript/jQuery, we can use
     $('.class="clsUser').length and it returns the length 2