CascadingDropdown.js

A vanilla javascript (ie. no additional libraries needed) plugin for cascading dropdown menus. This allows the values of an HTML <select> to be dependent on the value selected in a parent <select> element.

Demo

Demo

Usage

1. Include CascadingDropdown.js

<script src="CascadingDropdown.js"></script>

2. Add markup to <select>

• id: each <select> must have an id defined.
• class="cascadingDropdown": customizable in the plugin intialization options below.
• data-select-message="...": the text displayed in the default option.
• data-url: the URL for ajax requests.
• data-parent-fields: comma delimited list of ids that the current field is dependent on.

For example:

<h2>Car Inventory:</h2>
<form>
  <select id="Year" name="Year" class="cascadingDropdown" data-url="/Year" data-select-message="Select a year...">
  </select>
  <select id="Make" name="Make" class="cascadingDropdown" data-url="/Make" data-parent-fields="Year" data-select-message="Select a make...">
  </select>
  <select id="Model" name="Model" class="cascadingDropdown" data-url="/Model" data-parent-fields="Year,Make" data-select-message="Select a model...">
  </select>
</form>

3. Initialize

CascadingDropdown.init({
	selector:'.cascadingDropdown',
  	source: function(url,parms,callback) {
    		//A json array containing Text and Value properties for each option must be passed into the callback.
    		callback([{"Text":"First Value","Value":"1"},{"Text":"Second Value","Value":"2"}]);
  	}
});

License

The code is available under the MIT License.