How do I include Javascript inside PHP?

I'm trying to write some Javascript inside PHP, I made a simple button that takes you to the previous page. The button is showing but the functionality of the button isn't working. This is the code I have.

<?php
$product;
if (empty($product))
{
 echo
 '
 <script>
 function myFunction() {
 header("location:".history.go(-1));
 }
 </script>
 <button onclick=myFunction()>Click me</button>
 ';
 exit();
}

I go to my local server to the file where this code is and except it to work but it doesn't. For example, I go to http://127.0.0.1/test1.php where there is is a button (which works perfectly) that takes you to http://127.0.0.1/test2.php (where this this piece of code is). When I press the 'Click me' button, nothing happens. I'm wondering what I'm doing wrong? Or is it because It's local that the problems are caused? I've tried this in Chrome and Safari.

• 4
  You are mixing PHP and JavaScript. They are two completely different languages.

  Dharman

  – Dharman ♦

  2019年04月27日 12:25:12 +00:00

  Commented Apr 27, 2019 at 12:25
• 1
  @Dharman You're completely right! Thanks for pointing that out.

  user8577141

  – user8577141

  2019年04月27日 12:29:14 +00:00

  Commented Apr 27, 2019 at 12:29
• 3
  Check MDN article for Window.history. Take note of history.back()

  Tigger

  – Tigger

  2019年04月27日 12:29:36 +00:00

  Commented Apr 27, 2019 at 12:29

1 Answer 1