H5 is short for HTML5, which is a standard for creating web pages and mobile applications. JavaScript is a programming language that can be used to make web pages and applications more interactive and dynamic. So, where should we write JavaScript in H5 pages?
Generally speaking, JavaScript code can be embedded directly in the HTML document or introduced as an external file. These methods are also applicable in H5.
1. Embed JavaScript code into an HTML document
The easiest way to embed JavaScript code is to insert the code directly into the HTML file using the <script> tag. The following is an example: </script>
<html> <head> <title>我的H5页面</title> <script> function showMessage() { alert('欢迎光临我的页面!'); } </script> </head> <body> <button onclick="showMessage()">点我</button> </body> </html>
In this example, we define a function named showMessage. When the user clicks the button, the function will be called and a dialog box will pop up. As you can see, we have embedded the JavaScript code directly in the
tag of the HTML document.Of course, this method is not the best choice, because if our JavaScript code is very complex, or we need to use it in multiple places on the page, then this method will make the HTML document bloated. Unbearable. Next, let’s introduce another method.
2. Introduce JavaScript code as an external file
If we need to use the same JavaScript code in multiple pages, or our JavaScript code is very complex, then we can use the external file way to introduce it. The following is an example:
We create a file named hello.js in the same directory and define a function named showMessage in it. The code is as follows:
function showMessage() { alert('欢迎光临我的页面!'); }
Next , add the following code within the
tag of the HTML document:<html> <head> <title>我的H5页面</title> <script src="hello.js"></script> </head> <body> <button onclick="showMessage()">点我</button> </body> </html>
In this example, we use the src attribute of the <script> tag to introduce an external JavaScript file named hello.js. In this way, our JavaScript code can be shared by multiple pages, and the HTML code of the page is more concise. </script>
In short, in the H5 page, we can embed JavaScript code directly into the HTML document, or introduce it as an external file. Which method you choose depends on the complexity and sharing of your code.
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