Script defer attribute

Objet Script DOM HTML

Definition and Usage

defer whether the script should be executed when the page parsing is completed.

This attribute reflects <script> tag of defer attribute.

Note:The defer attribute is only applicable to external scripts (and should only be used when setting the src attribute).

Note:There are several ways to execute external scripts:

  • If async is present: Execute the script asynchronously with the rest of the page (the script will be executed while the page continues to parse)
  • If async is not present and defer is present: Execute the script when the page parsing is completed
  • If neither async nor defer is present: Execute the script immediately before the browser continues parsing the page

See also:

HTML Reference Manual:Attribut defer de la balise <script> HTML

HTML Reference Manual:Balise <script> HTML

Example

Determine whether the script was executed when the page parsing was completed:

var x = document.getElementById("myScript").defer

Try it yourself

Syntax

Return the defer attribute:

scriptObject.defer

Set the defer attribute:

scriptObject.defer = true|false

attribute value

value description
true|false

Définit si le script doit s'exécuter lorsque la page est complètement analysée.

  • true - Le script s'exécute lorsque la page est complètement analysée
  • false - Le script ne s'exécute pas après la fin de l'analyse de la page

Détails techniques

Valeur de retour : Valeur booléenne, retourne true si le script s'exécute après la fin de l'analyse de la page ; sinon retourne false.

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Objet Script DOM HTML