将javascript嵌入php代码

Question

I have embedded some javascript within php code. This was necessary after checking some php session variable value, and upon result, I use some JS within php to decide if some elements will be shown or not. Here is an example:

<?php

if ($_SESSION['myVar']==2)
      { echo '<script type="text/javascript" >

          document.getElementById("element1").style.visibility = "hidden";
         document.getElementById("element2").style.visibility = "hidden";

            </script>';
?>

The code works perfect for me. My question is : is the JS executed at the webserver(since it is embedded within php code) , initializing the page before it is sent to the client browser (and that what I think), or does the php portion run at the server, and the JS runs at the client later??

I know in normal situations the JS runs at the client browser,but was suspicious in this case,

I'm a junior programmer and any help is appreciated, thanks in advance.

Answer 1

Javascript is always executed in the browser of the client. The php code just inserts the javascript code as a block of text and the browser reads it as code.

Answer 2

不管怎样，JavaScript都是在客户端执行的，但是您只是在PHP代码中插入了代码，以使浏览器可以执行它。

Answer 3

Php sends the JavaScript back to the Client as a response and then on the Client side JavaScript is run. Please read this ANSWER 123 and you might have a better explanation >> PHP & Embedded JavaScript Behavior . Thanks

Answer 4

<?php

if ($_SESSION['myVar']==2)
      { 
?>
<script type="text/javascript" >
      document.getElementById("element1").style.visibility = "hidden";
         document.getElementById("element2").style.visibility = "hidden";
</script>
<?php } ?>