PHP变量到Javascript输出PHP代码

Question

For some reason, when passing a php variable to javascript using the following code.

JS:

var myVar = "<?php echo $pass ?>";
document.getElementById("output").innerHTML = myVar;
console.log(myVar);

And the PHP:

<?php
$myfile = fopen("testfile.txt", "r");
$pass = fread($myfile,filesize("testfile.txt"));
fclose($myfile);
?>

But instead of outputting the text in the file, "This is some text", it outputs the raw php code and not executing it: "

When looking at the p element in the Inspector, it is this:

<p id="output"><!--?php echo $pass;?--></p>

Answer 1

You cannot put PHP code into a javascript file that is run on the client's computer. PHP is interpreted on the server side, and generally speaking, only in .php files.