up.form up:form:switch

DOM event

When an [up-switch] field changes, this event is emitted on all dependent elements.

You can listen to up:form:switch to implement custom switching effects.

Event targets

This event is not emitted on the switching field. Instead each element matching the switch selector will receive an up:form:switch event:

<!-- Switching field won't receive an event on change -->
<select name="role" up-switch=".role-dependent">
  <option value="trainee">Trainee</option>
  <option value="manager">Manager</option>
</select>

<!-- Dependent field will receive up:form:switch -->
<input class="role-dependent" name="department">

<!-- Dependent field will receive up:form:switch -->
<input class="role-dependent" name="budget">

Timing

The up:form:switch is emitted at the following times:

• when the switching field is initially rendered.
• after a switching field has changed its value.
• after a switching checkbox was checked or unchecked.
• when a new selector match enters the form.
• when a kept [up-switch] field is transported to a new form.