onload-begivenhed

DOM events Event objekt

Definition og brug

onload-begivenheden opstår efter at objektet er indlæst.

onload bruges oftest i <body>-elementet, og bruges til at udføre scripts efter at websiden er fuldt indlæst (inklusive billeder, skriptfiler, CSS-filer osv.).

onload begivenhed kan bruges til at kontrollere besøgendes browser-type og version, og derefter indlæse den korrekte version af websiden baseret på denne information.

The onload event can also be used to handle cookies (see more examples below).

Example

Execute JavaScript immediately after page load:

<body onload="myFunction()">

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Example 2

Use onload on <img> element. Alert 'Image is loaded' immediately after the image is loaded:

<img src="w3javascript.gif" onload="loadImage()" width="100" height="132">
<script>
function loadImage() {
  alert("Image is loaded");
}
</script>

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Example 3

Use onload event to handle cookies:

<body onload="checkCookies()">
<script>
function checkCookies() {
  var text = "";
  if (navigator.cookieEnabled == true) {
    text = "Cookies are enabled.";
  } else {
     text = "Cookies are not enabled.";
  }
  document.getElementById("demo").innerHTML = text;
}
</script>

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Syntax

In HTML:

<element onload="myScript">

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In JavaScript:

object.onload = function(){myScript};

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In JavaScript, use the addEventListener() method:

object.addEventListener("load", myScript);

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Note:Internet Explorer 8 or earlier versions do not support addEventListener() method.

Technical details

Bubble: Not supported
Cancelable: Not supported
Event type: If generated from the user interfaceUiEvent. Otherwise Event.
Supported HTML tags: <body>, <frame>, <iframe>, <img>, <input type="image">, <link>, <script>, <style>
DOM version: Level 2 Events

Browserv understøttelse

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DOM events Event objekt