How to Ensure Global Variable Accessibility Across Multiple JavaScript Files?

Accessing Global Variables Across Multiple JavaScript Files

You are facing a challenge in accessing a global variable from an external JavaScript file (helpers.js) within your HTML code. You have tried defining a global variable (myFunctionTag) in both the HTML and helpers.js, but it appears as false in the HTML despite being set to true in helpers.js.

To resolve this issue, the key lies in understanding how global variables are defined and accessed in JavaScript. When a global variable is declared within a function or block of code, it becomes scoped within that function or block. To make it accessible across multiple files, the variable must be defined outside any functions or blocks, typically at the beginning of the script.

In this specific case, the problem arises because you are declaring the myFunctionTag variable inside the <script> tag in the HTML. When the HTML is parsed and the code from helpers.js is loaded, the myFunctionTag variable declared in the HTML is already in scope. However, because the version in helpers.js is defined later, it overrides the one in the HTML, causing it to be false even after it has been set to true in helpers.js.</script>

To fix this, you should declare the myFunctionTag variable before including the helpers.js file. Here's the corrected code:

<code class="html"><script type="text/javascript">
  var myFunctionTag = false;
</script>
<script type="text/javascript" src="js/helpers.js"></script>

<script type="text/javascript">
  // Rest of your code that may depend on helpers.js
</script></code>

By declaring myFunctionTag outside any functions or blocks before loading helpers.js, you ensure that the same global variable is accessible across both files.

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