HTML JavaScript

JavaScript gør HTML-sider mere dynamiske og interaktive

Example

Mit første JavaScript

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HTML <script> tag

HTML <script> tagget bruges til at definere klient-side skript (JavaScript).

<script> element kan indeholde skriptinstruktioner, og de kan også bruge src egenskab peger på en ekstern skriptfil.

De almindelige anvendelser af JavaScript er billedbehandling, formularvalidering og dynamisk indhold.

For at vælge HTML-elementer er JavaScript mest brugt document.getElementById() metoder.

Dette JavaScript-eksempel skriver "Hello JavaScript!" til HTML-elementet med id="demo":

Example

<script>
document.getElementById("demo").innerHTML = "Hello JavaScript!";
</script>

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Tip:Du kan finde vores JavaScript tutorial lær mere om JavaScript.

Smagen af JavaScript

Her er nogle eksempler på, hvordan JavaScript kan bruges:

Example

JavaScript can change content:

document.getElementById("demo").innerHTML = "Hello JavaScript!";

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Example

JavaScript can change styles:

document.getElementById("demo").style.fontSize = "25px";
document.getElementById("demo").style.color = "red";
document.getElementById("demo").style.backgroundColor = "yellow";

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Example

JavaScript can change properties:

document.getElementById("image").src = "picture.gif";

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HTML <noscript> tag

HTML <noscript> The tag defines alternative content that will be displayed to users who have disabled scripts in the browser or whose browser does not support scripts:

Example

<script>
document.getElementById("demo").innerHTML = "Hello JavaScript!";
</script>
<noscript>Sorry, your browser does not support JavaScript!</noscript>

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HTML Script tag

Tag Description
<script> Define client-side scripts.
<noscript> Define alternative content for users who do not support client-side scripts.

For a complete list of all available HTML tags, please visit our HTML tag reference manual.