Attribut HTML id
L’attribut id est utilisé pour définir un identifiant unique pour un élément HTML. Il est couramment utilisé pour cibler un style dans une feuille de style, ainsi que pour les liens d’ancrage et les cibles des scripts. La valeur de id est sensible à la casse et doit être unique dans le document HTML.
Cet attribut peut être utilisé par CSS et JavaScript (via le DOM HTML) pour effectuer des tâches spécifiques sur l’élément ayant l’id spécifié.
En CSS, vous devez écrire un caractère dièse (#) suivi de l’id de l’élément pour sélectionner l’élément ayant un id spécifié. Il doit comporter au moins un caractère et ne doit pas contenir d’espaces blancs (tabulations, espaces, etc.).
En HTML5, l’attribut id peut être utilisé pour n’importe quel élément HTML.
En HTML 4.01, l’attribut id ne peut pas être utilisé avec les éléments suivants : <head>, <html>, <base>, <param>, <style>, <script>, et <title>.
Syntaxe
Syntaxe de l’attribut HTML id
html
<tag id="id"></tag>Exemple de l’attribut HTML id :
Exemple de l’attribut HTML id :
html
<!DOCTYPE html>
<html>
<head>
<title>Title of the document</title>
<style>
#grey {
color: grey;
}
#purple {
color: purple;
}
</style>
</head>
<body>
<h1>Example of the HTML id attribute</h1>
<p id="grey">
It is a grey paragraph.
</p>
<p>This is some text.</p>
<p id="purple">
It is a purple paragraph.
</p>
</body>
</html>Un élément HTML ne peut avoir qu’un seul id unique appartenant à cet élément unique, contrairement à l’attribut class, où un nom de classe peut être utilisé par plusieurs éléments.
Exemple des attributs HTML id et class :
Exemple des attributs HTML "id" et "class" :
html
<!DOCTYPE html>
<html>
<head>
<title>Title of the document</title>
<style>
#green-bg {
background-color: green;
color: white;
padding: 20px;
text-align: center;
}
.text-grey {
color: grey;
padding: 5px 15px;
}
</style>
</head>
<body>
<h1>Example of the HTML "id" and "class" attributes:</h1>
<p>
Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book.
</p>
<h2 id="green-bg">HTML ID attribute</h2>
<p class="text-grey">
Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs.
</p>
<p class="text-grey">
Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book
</p>
<p class="text-grey">
The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book.
</p>
</body>
</html>Signets
Vous pouvez utiliser des signets HTML pour permettre aux lecteurs d’accéder à d’autres parties d’une page web lorsqu’elle est trop longue.
Pour ajouter un signet, créez d’abord le signet, puis ajoutez-lui un lien. Lorsque vous cliquez sur le lien, la page défilera jusqu’à la partie contenant le signet.
Exemple d’ajout d’un signet :
Exemple d’ajout d’un signet :
html
<!DOCTYPE html>
<html>
<head>
<title>Title of the document</title>
<style>
p {
line-height: 1.5;
color: #777777;
}
a {
color: #20c7c1;
display: inline-block;
padding: 5px 15px;
}
strong {
display: block;
color: #1129dc;
}
</style>
</head>
<body>
<h1>Example of the HTML "id" and "class" attributes:</h1>
<p>Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book.</p>
<a href="#text2">Jump to the text-2</a>
<a href="#text3">Jump to the text-3</a>
<p id="text-1">
<strong>Text number 1</strong> Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs.
</p>
<p id="text2">
<strong>Text number 2</strong> Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book. Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book
</p>
<p id="text3">
<strong>Text number 3</strong> Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book.
</p>
<p>
<strong>Text number 4</strong> Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book.
</p>
<p>
<strong>Text number 5</strong> Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book Lorem ipsum, or lipsum as it is sometimes known, is dummy text used in laying out print, graphic or web designs. The passage is attributed to an unknown typesetter in the 15th century who is thought to have scrambled parts of Cicero's De Finibus Bonorum et Malorum for use in a type specimen book.
</p>
</body>
</html>Pratique
Quelles sont les caractéristiques et les utilisations de l’attribut HTML 'id' ?