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How to enable javascript

PHPz

Release： 2023-04-25 14:03:47

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JavaScript is a scripting language widely used in web pages. It can achieve dynamic effects, interactivity and practicality in web pages. If you want to use JavaScript in your web pages, you need to know how to enable it.

In this article, we will discuss how JavaScript is enabled and how to choose the appropriate way to enable it.

1. Inline script

The easiest way to use JavaScript in a web page is through inline script. Inline script is JavaScript code embedded directly into the HTML tags of a web page. For example:

<!DOCTYPE html>
<html>
  <head>
    <title>JavaScript Example</title>
  </head>
  <body>
    <h1>Hello, World!</h1>
    <button onclick="alert(&#39;Hello, World!&#39;)">Click me</button>
  </body>
</html>

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In this example, we enable JavaScript by adding the onclick attribute on the button tag. When the user clicks the button, a message box pops up with the text "Hello, World!"

Although inline scripting is very simple and easy to use, it also has some disadvantages. First, it makes the code difficult to maintain because JavaScript code is mixed with HTML. Secondly, it is inconvenient to reuse JavaScript code, because each page that needs to use the code needs to manually add the corresponding code.

2. Internal scripts

Another way to enable JavaScript is to use internal scripts. Internal scripts are JavaScript code embedded directly into the HTML tags of a web page. For example:

<!DOCTYPE html>
<html>
  <head>
    <title>JavaScript Example</title>
    <script>
      function showMessage() {
        alert('Hello, World!');
      }
    </script>
  </head>
  <body>
    <h1>Hello, World!</h1>
    <button onclick="showMessage()">Click me</button>
  </body>
</html>

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In this example, we embed the JavaScript code into the head tag. Then, we added the onclick attribute on the button label, which will call the showMessage function to pop up a message box when the user clicks the button.

Using internal scripts allows us to separate JavaScript code from HTML, making the code easier to maintain. But similar to inline scripts, it still requires manually adding the corresponding code on each page that requires it.

3. External scripts

Using external scripts is one of the most common ways to enable JavaScript. An external script is a separate JavaScript file that can be reused by multiple pages. For example:

<!DOCTYPE html>
<html>
  <head>
    <title>JavaScript Example</title>
    <script src="script.js" defer></script>
  </head>
  <body>
    <h1>Hello, World!</h1>
    <button onClick="showMessage()">Click me</button>
  </body>
</html>

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In this example, we added a script tag in the head tag that points to the script.js file. In the script.js file, we define the showMessage function. Then, we added the onclick attribute on the button tag, which will call the showMessage function.

Note: We also added the defer attribute, which causes the JavaScript file to be executed after the HTML document is parsed, thereby ensuring that the code does not block the loading of other content.

Using external scripts allows us to completely separate JavaScript code from HTML, making the code clearer and easier to understand, and can be easily reused on multiple pages.

Summary

There are many ways to enable JavaScript. Inline scripting is the easiest way to enable it, but it is also the least desirable because it makes it difficult to maintain and reuse the code. Internal scripts can separate the code from the HTML, but you still need to add the code manually on each page. External scripting is the best way to enable JavaScript because it completely separates the code from the HTML and can be easily reused on multiple pages.

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