How to call a JavaScript file inside a PHP if/else statement?

Question

I have to call different JavaScript files depending on the users choice from a dropdown menu.

I tried to do it like this:

if ($subject == "Chemistry") {
  '<script src="ChartJS_Chemistry></script>';
}

But that doesn't seem to work.

Any advice on how to activate the right file depending on the dropdown menu choice?

sam · Accepted Answer · 2019-06-14 21:30:11Z

3

As commented, you did not echo anything out.

But also your syntax is wrong:

'<script src="ChartJS_Chemistry></script>';

You're missing " and I am assuming you're also missing a file extension?

It should be something like:

echo '<script src="ChartJS_Chemistry.js"></script>';

Also; this is not best practice. Close your PHP tag then write the script tag in HTML:

<?php if( true ) { ?>
  <script src="ChartJS_Chemistry.js"></script>
<?php } ?>

Since then you'r not mixing your PHP with HTML - not good practice.

answered Jun 14, 2019 at 21:30

sam

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Comments

Hudson Cantuária · Accepted Answer · 2019-06-14 21:30:52Z

0

your file path is broken, if your file is ChartJS_Chemistry.js

Call like.

if ($subject == "Chemistry") {
    echo "<script src='ChartJS_Chemistry.js'></script>";
}

answered Jun 14, 2019 at 21:30

Hudson Cantuária

514 bronze badges

Nitesh Garg · Accepted Answer · 2019-06-15 06:05:47Z

0

if ($subject == "Chemistry") {
        //close php tag here 
?> 
   <script src="ChartJS_Chemistry"></script>
<?php //start php tag again here
}

answered Jun 15, 2019 at 6:05

Nitesh Garg

1793 bronze badges