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How to create dynamic web pages with javascript

PHPz

Release： 2023-04-24 10:25:25

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In modern front-end development, JavaScript plays an indispensable role. It provides us with endless possibilities, allowing web pages to dynamically change according to user behavior and needs. JavaScript dynamic web pages mean that web pages can dynamically display, hide, change content, add elements, etc. This article will introduce how to use JavaScript to create dynamic web pages.

1. Introduction of JavaScript

JavaScript code can be embedded in HTML code or imported from an external JavaScript file. In order to strip and maintain the code, it is recommended to put the JavaScript code in a separate external file and introduce it through the Script tag, for example:

<!DOCTYPE html>
<html>
<head>
    <title>JavaScript 动态网页</title>
    <script type="text/javascript" src="path/to/your/js/file.js"></script>
</head>
<body>
    <!-- Your HTML code here -->
</body>
</html>

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2. Event monitoring

When developing dynamic web pages When producing, we need to monitor user behaviors (such as clicks, hovers, etc.) and make corresponding dynamic effects. At this time, we need to use event listeners in JavaScript. For example, to add a click event to a button and change its font color, the code is as follows:

var myButton = document.getElementById('myButton');
myButton.addEventListener('click', function() {
    myButton.style.color = 'red';
});

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In the above code, myButton is a DOM element object, which passes getElementById Method to obtain. Then, we added a click event listener to it through the addEventListener method. When the user clicks the button, JavaScript executes the code in the callback function and sets the button font color to red. Through this method, we can link various interactive actions with dynamic effects to implement JavaScript dynamic web pages.

3. DOM operations

In JavaScript, each element in the web page is regarded as an object. These objects are called DOM (Document Object Model) objects. We can directly operate on these objects to modify web pages.

For example, we can dynamically create, add, and delete web page elements through JavaScript. The following code implements dynamically adding a paragraph:

var myParagraph = document.createElement('p');
myParagraph.innerHTML = '这是新添加的段落';
var contentArea = document.getElementByClassName('content')[0];
contentarea.appendChild(myParagraph);

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In the above code, the createElement method creates a p element object myParagraph, and then gives it Assign the innerHTML attribute and finally add it to the HTML via the appendChild method. Through DOM operations, we can achieve effects such as dynamically adding, moving, modifying, and deleting elements, making web pages more dynamic.

4. jQuery library

jQuery is a widely used JavaScript function library that can greatly simplify JavaScript code. By using jQuery, we can easily implement JavaScript dynamic web pages.

The following is an example of changing the color of an element with jQuery:

$(document).ready(function(){
    $('#button').click(function(){
        $(this).css('color', 'red');
    });
});

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In the above code, we use the document.ready function, which means that when the HTML document is loaded, execute code within this function. Then we added a click event listener to the element with the id button, and when the user clicks the button, set its font color to red. Through jQuery, we can implement JavaScript dynamic web pages more concisely and accurately.

Summary

This article introduces the method of making JavaScript dynamic web pages, including the introduction of JavaScript, event listening, DOM operations and jQuery library. When designing dynamic web pages, we need to use the above methods to develop based on user needs to make the web pages more interactive and friendly and improve the user experience.

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