Calling JS from PHP

[cesarcesar]

how do i get JS call to work from within a PHP page. Here is my stripped code. please note the multiple file names.

 

file1.php - calls JS function in file2.js (working fine).

file2.js - makes http_request to file3.php to do some stuff. (working fine)

file3.php - check some stuff in the db (working), then makes the following JS call to a <span> in file1.php (not working)

echo" <script language=Javascript><!--";
echo" document.getElementById('email_hint').style.visibility = 'visible';";
echo" //--></script>";

 

file1.php <span> tag

<span id="email_hint" style="visibility:hidden;">Email all ready assigned to a member.</span>

 

My questions is why does the <span> never hear/process the getElementById call? Could it be that the call to the *document.* only refers to elements in file3.php? What say you?

 

FYI, file3.php is all php, it has no HTML.

[cesarcesar]

SOLUTION - Thanks to *Stryker250* and all other who helped me get on the right track.

 

(FYI.. trim() function is part of this lib - PHP to Javascript Project, http://kevin.vanzonneveld.net/techblog/article/phpjs_licensing/)

 

file2.js - Listened for the XHR "responseText" value sent back from the requested page. Depending on the reply, I did something.

        if (trim(http_request.responseText)=='email'){
            document.getElementById('email_hint').style.visibility = 'visible';
        }else if(trim(http_request.responseText)=='email_new'){
            document.getElementById('email_hint').style.visibility = 'hidden';
        }

file3.php - Depending on what was PHP'd from data send by file2.js, I echo'd either "email" or "email_new". (As is in my script, nothing else can be echo'd on the page.)