为什么PHP无法进入本地存储？

Question

Why is it that in php you can open up a script tag like so and do the following:

<?php
  print("<script>");
  print("alert('hey');");
  print("</script>");
?>

but you can't do this:

<?php 
  print("<script>");
  print("document.getElementById('fName').value = localStorage.getItem('FirstName');");
  print("</script>"); 
?>

I just can't understand what the difference is, if you can get javascript to work inside php, why can't you tap into localstorage?

Answer 1

There is no dependency on the content of the Javascript. PHP does not "filter" your output and your browser won't recognize that it has been the output of a PHP script.

Does the script work if you don't output it that way and instead write it statically into your document? Please note that the script does not automatically add line breaks and possibly procudes invalid Javascript code if you forget the semicolon.

Can you paste the output of your browser's error console?