How to Auto-Update Options in a Second Drop Down Menu Based on Selections in the First Drop Down Menu?

First Drop Down Menu Auto-updates Options in Second Drop Down Menu

Problem Statement:

Develop two drop-down menus where the options in the second drop-down menu depend on the selection made in the first drop-down menu. This functionality is desired without utilizing a database.

Solution:

Initial HTML:

<code class="html"><select id="category">
  <option value="0">None</option>
  <option value="1">First</option>
  <option value="2">Second</option>
  <option value="3">Third</option>
  <option value="4">Fourth</option>
</select>

<select id="items">
</select></code>

JavaScript:

Define a function to handle the change event of the first drop-down menu and update the options in the second drop-down menu accordingly.

<code class="javascript">document.getElementById("category").addEventListener("change", function() {
  var category = this.value;

  var items = document.getElementById("items");
  items.innerHTML = "";

  switch (category) {
    case "1":
      items.innerHTML = '<option value="3">Smartphone</option><option value="8">Charger</option>';
      break;
    case "2":
      items.innerHTML = '<option value="1">Basketball</option><option value="4">Volleyball</option>';
      break;
    default:
      break;
  }
});</code>

Explanation:

In this example, the options for the second drop-down menu are hardcoded within the JavaScript function. When the user selects a category from the first drop-down menu, the change event triggers the JavaScript function. Based on the selected category, the function dynamically updates the options in the second drop-down menu.

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