What are some examples of dynamic form controls?

What are some examples of dynamic form controls?

Dynamic form controls are elements that change based on user input. Examples include dropdowns that update options based on previous selections, or fields that appear when certain conditions are met.

Can you give me a specific example of a dynamic dropdown?

Sure! Imagine a form where a user selects a country from a dropdown. Once they select a country, a second dropdown appears with states or provinces specific to that country.

How can I implement this in HTML and JavaScript?

You can use JavaScript to listen for changes on the first dropdown and then populate the second dropdown based on the selected country. Would you like a code snippet?

Yes, please provide a code snippet!

Here's a simple example:

<select id="country" onchange="updateStates()">
  <option value="">Select a country</option>
  <option value="usa">USA</option>
  <option value="canada">Canada</option>
</select>

<select id="state"></select>

<script>
function updateStates() {
  const country = document.getElementById('country').value;
  const stateDropdown = document.getElementById('state');
  stateDropdown.innerHTML = '';

  if (country === 'usa') {
    stateDropdown.innerHTML = '<option value="ny">New York</option><option value="ca">California</option>';
  } else if (country === 'canada') {
    stateDropdown.innerHTML = '<option value="on">Ontario</option><option value="qc">Quebec</option>';
  }
}
</script>

This will dynamically update the states based on the selected country.