Forms and JavaScript: Inspect the value of an item

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In this unit I’ll show you how to use JavaScript to interact with a form.

Let’s start with the simple form we defined in the Introduction to Forms unit:

<form>
  <input type="text" name="city" />
</form>

Using the DOM API and in particular querySelector, we can get the value typed into this input field:

document.querySelector('input').value

This is often used along with events.

Lessons in this unit:

0: Introduction
1: ▶︎ Inspect the value of an item
2: Listen to events on input fields
3: Intercepting a form submit event using JavaScript
4: Redirect to a link when user selects option in a select