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Baransel
Baransel

Posted on • Originally published at baransel.dev

How to run Javascript

#softwareengineering #development #documentation

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Since JavaScript commands run on the browser, we need to add JavaScript codes to our web page.

There are various methods of adding JavaScript code to a web page.

JavaScript codes can be written between the <script> and </script> tags.

<script>
   alert("baransel.dev");
</script>
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It can be written to HTML properties such as onclick, which indicates when the HTML element is clicked, onmouseover, which indicates that the HTML element is hovered.

<button onclick="alert('baransel.dev')">Click</button>
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After the JavaScript codes are written to the external .js file, the <script> tag can be written to the src property by specifying the file name.

JavaScript codes (example.js) 

alert("baransel.dev");
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HTML Codes 

<script src="example.js"></script>
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Codes are written to the external JavaScript file without the <script> and </script> tags.

Written JavaScript codes can be inserted into <head> or <body> tags.

<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <title>Baransel Arslan</title>
</head>

<body>
  <script>
    alert("baransel.dev");
  </script>
</body>

</html>
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Long JavaScript commands can slow down the page load.

If the codes in the page or in external JavaScript files are added to the end of the <body> tag, the page will open faster.

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