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14.7 JS DOM CSS

The HTML DOM allows JavaScript to change the style of HTML elements.

Changing HTML Style

To change the style of an HTML element, use this syntax:

document.getElementById(id).style.property = new style

The following example changes the style of a <p> element:

Example 1: JS HTML DOM - Changing the HTML style

<html>
<body>

<p id="p2">Hello World!</p>

<script>
document.getElementById("p2").style.color = "blue";
</script>

<p>The paragraph above was changed by a script.</p>

</body>
</html>

Using Events

The HTML DOM allows you to execute code when an event occurs.
Events are generated by the browser when "things happen" to HTML elements:
- An element is clicked on
- The page has loaded
- Input fields are changed
You will learn more about events in the next chapter of this tutorial.
This example changes the style of the HTML element with id="id1", when the user clicks a button:

Example 2: JS HTML DOM - Changing the HTML style Using Events

<!DOCTYPE html>
<html>
<body>

<h1 id="id1">My Heading 1</h1>

<button type="button"
onclick="document.getElementById('id1').style.color = 'red'">
Click Me!</button>

</body>
</html>

More Examples

Visibility How to make an element invisible. Do you want to show the element or not?

HTML DOM Style Object Reference

For all HTML DOM style properties, look at W3Schools.com complete HTML DOM Style Object Reference.

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Module 14. JS HTML DOM

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Example files created in this module:
HTML DOM Methods JS HTML DOM - Finding HTML Element by Id JS HTML DOM - Finding HTML Elements by Tag Name part 1 JS HTML DOM - Finding HTML Elements by Tag Name part 2 JS HTML DOM - Finding HTML Elements by Class Name JS HTML DOM - Finding HTML Elements by CSS Selectors JS HTML DOM - Finding HTML Elements by HTML document.forms JS Changing HTML Content part 1 JS Changing HTML Content part 2 JS HTML DOM - Changing the Value of an Attribute JS HTML DOM - Dynamic HTML content JS HTML DOM - document.write() JS Validation - HTML Form Example part 1 JS Validation - HTML Form Example part 2 JS HTML DOM - Changing the HTML style JS HTML DOM - Changing the HTML style Using Events My first JS animation part 1 My first JS animation part 2 JS HTML Events - The onclick Attribute part 1 JS HTML Events - The onclick Attribute part 2 JS HTML Events - The onclick Attribute part 3 JS HTML Events - The onclick Attribute part 4 JS HTML Events - The onload Attribute JS addEventListener() part 1 JS addEventListener() part 2 JS addEventListener() part 3 JS addEventListener() part 4 JS addEventListener() part 5 JS addEventListener() part 6 JS addEventListener() part 7 JS addEventListener() part 8 JS removeEventListener() JS HTML Child Nodes and Node Values part 1 JS HTML Child Nodes and Node Values part 2 JS HTML Child Nodes and Node Values part 3 JS HTMLDOM - DOM Root Nodes part 1 JS HTMLDOM - DOM Root Nodes part 2 JS HTMLDOM - The nodeName Property JS HTMLDOM - The nodeType Property JS HTML DOM - Creating New HTML Elements (Nodes) JS HTML DOM - Creating new HTML Elements - insertBefore() JS HTML DOM - Removing Existing HTML Elements JS HTML DOM - Remove Child Element JS HTML DOM - Replacing an HTML Elements JS HTML DOM Collections JS HTML DOM Collections - HTMLCollection Length par 1 JS HTML DOM Collections - HTMLCollection Length part 2 JS HTML DOM - DOM Node Lists JS HTML DOM - DOM Node List Length part 1 JS HTML DOM - DOM Node List Length part 2