How to declare custom attributes in HTML?
Aug 21, 2023 am 08:37 AM
In this article, we will discuss how to declare a custom attribute in HTML. Custom attributes can be useful in HTML when you want to store some additional information that is not part of the standard HTML attributes. It allows for more flexibility and customization in HTML and can help make your code more maintainable and understandable.
Approaches
We have two different approaches to declaring a custom attribute in HTML including the following ?
使用“ data- 前綴”
使用“自定義前綴”
讓我們?cè)敿?xì)看一下每個(gè)步驟。
方法：使用“data-前綴方法”
第一種方法是在HTML中聲明一個(gè)自定義屬性，使用“data-”前綴。我們可以通過在屬性名前加上"data-"來定義自定義屬性。您可以使用自己選擇的前綴來創(chuàng)建自定義屬性的名稱。這樣可以將特定數(shù)據(jù)附加到HTML元素上，可以很容易地使用CSS、JavaScript或jQuery來定位。
Example
以下是使用“data-前綴”在HTML中聲明自定義屬性的示例。
<!DOCTYPE html>
<html>
<head>
<title>Employee Table</title>
<style>
h1 {
color: blue;
}
th {
color: red;
}
table {
border-collapse: collapse;
width: 100%;
}
th, td {
padding: 5px;
text-align: left;
border-bottom: 1px solid #ddd;
}
tr:nth-child(even) {
background-color: #f2f2f2;
}
</style>
</head>
<body>
<h1>Employee Table</h1>
<table>
<thead>
<tr>
<th>Employee ID</th>
<th>Name</th>
<th>Department</th>
<th>Salary</th>
</tr>
</thead>
<tbody>
<tr data-empid="001" data-dept="IT" data-salary="75000">
<td>001</td>
<td>Taylor</td>
<td>IT</td>
<td>$75,000</td>
</tr>
<tr data-empid="002" data-dept="HR" data-salary="60000">
<td>002</td>
<td>Jhon</td>
<td>HR</td>
<td>$60,000</td>
</tr>
</tbody>
</table>
<script>
const rows = document.querySelectorAll("tr[data-empid]");
rows.forEach(row => {
const empid = row.dataset.empid;
const dept = row.dataset.dept;
const salary = row.dataset.salary;
console.log(`Employee ID: ${empid}, Department: ${dept}, Salary: ${salary}`);
});
</script>
</body>
</html>
Note ? Here, JavaScript can access the custom attributes in the example code by selecting the "tr" elements based on their custom attributes, and then logging the values of those attributes to the console.
方法：使用“自定義前綴方法”
第一種方法是在HTML中聲明一個(gè)自定義屬性作為“自定義前綴”。在HTML中，自定義前綴指的是在HTML元素上創(chuàng)建自定義屬性。前綴可以是您選擇的任何名稱，添加在屬性名稱之前，它可以用于向元素添加附加數(shù)據(jù)或信息。通過使用自定義前綴，您可以創(chuàng)建適用于您需求的自定義屬性，并可以在CSS或JavaScript中進(jìn)行定位。
Example
Following is an example of declaring a custom attribute in HTML using “custom prefix”.
<!DOCTYPE html>
<html>
<head>
<title>Custom Attribute Example</title>
<style>
[custom] {
color: red;
}
</style>
</head>
<body>
<h1 custom="header-color">Tutorials point</h1>
<p custom="paragraph-color">Hello World!</p>
<script>
const header = document.querySelector("[custom='header-color']");
const paragraph = document.querySelector("[custom='paragraph-color']")
console.log(`Header color: ${header.getAttribute('custom')}`);
console.log(`Paragraph color: ${paragraph.getAttribute('custom')}`);
</script>
</body>
</html>
It defines a custom attribute named "custom" and applies the CSS style to any element with that attribute.The JavaScript code selects the header and paragraph elements based on their custom attributes and logs the values of those attributes.
Conclusion
在本文中，我們研究了在HTML中聲明自定義屬性的兩種不同方法。在這里，我們使用了“data-前綴”和“自定義前綴”這兩種不同的方法。自定義前綴和data-前綴都用于在HTML中聲明自定義屬性，但是data-前綴更廣泛被認(rèn)可，并且被所有現(xiàn)代瀏覽器支持。自定義前綴更靈活，因?yàn)樗试S您選擇自己的前綴名稱，但是它可能不被所有瀏覽器或工具認(rèn)可。
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