how to execute php code within javascript

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Answer 1

Interaction of Javascript and PHP

We all grew up knowing that Javascript ran on the Client Side (ie the browser) and PHP was a server side tool (ie the Server side). CLEARLY the two just cant interact.

But -- good news; it can be made to work and here's how.

The objective is to get some dynamic info (say server configuration items) from the server into the Javascript environment so it can be used when needed - - typically this implies DHTML modification to the presentation.

First, to clarify the DHTML usage I'll cite this DHTML example:

<script type="text/javascript">

function updateContent() {
 var frameObj = document.getElementById("frameContent");
 var y = (frameObj.contentWindow || frameObj.contentDocument);

 if (y.document) y = y.document;
 y.body.style.backgroundColor="red";  // demonstration of failure to alter the display

 // create a default, simplistic alteration usinga fixed string.
 var textMsg = 'Say good night Gracy';

 y.write(textMsg);

 y.body.style.backgroundColor="#00ee00";  // visual confirmation that the updateContent() was effective

}
</script>

Assuming we have an html file with the ID="frameContent" somewhere, then we can alter the display with a simple < body onload="updateContent()" >

Golly gee; we don't need PHP to do that now do we! But that creates a structure for applying PHP provided content.

We change the webpage in question into a PHTML type to allow the server side PHP access to the content:

**foo.html becomes foo.phtml**

and we add to the top of that page. We also cause the php data to be loaded into globals for later access - - like this:

<?php
   global $msg1, $msg2, $textMsgPHP;

function getContent($filename) {
    if ($theData = file_get_contents($filename, FALSE)) {
        return "$theData";
    } else {
        echo "FAILED!";
        }
}
function returnContent($filename) {

  if ( $theData = getContent($filename) ) {
    // this works ONLY if $theData is one linear line (ie remove all \n)
    $textPHP = trim(preg_replace('/\r\n|\r|\n/', '', $theData));
    return "$textPHP";
  } else {
    echo '<span class="ERR">Error opening source file :(\n</span>';  # $filename!\n";
  } 
}

// preload the dynamic contents now for use later in the javascript (somewhere)
$msg1 =       returnContent('dummy_frame_data.txt');
$msg2 =       returnContent('dummy_frame_data_0.txt');
$textMsgPHP = returnContent('dummy_frame_data_1.txt');

?>

Now our javascripts can get to the PHP globals like this:

// by accessig the globals var textMsg = '< ? php global $textMsgPHP; echo "$textMsgPHP"; ? >';

In the javascript, replace

var textMsg = 'Say good night Gracy';

with: // using php returnContent()

var textMsg = '< ? php $msgX = returnContent('dummy_div_data_3.txt'); echo "$msgX" ? >';

Summary:

• the webpage to be modified MUST be a phtml or some php file
• the first thing in that file MUST be the < ? php to get the dynamic data ?>
• the php data MUST contain its own css styling (if content is in a frame)
• the javascript to use the dynamic data must be in this same file
• and we drop in/outof PHP as necessary to access the dynamic data
• Notice:- use single quotes in the outer javascript and ONLY double quotes in the dynamic php data

To be resolved: calling updateContent() with a filename and using it via onClick() instead of onLoad()

An example could be provided in the Sample_Dynamic_Frame.zip for your inspection, but didn't find a means to attach it

Answer 2

You can't run PHP with javascript. JavaScript is a client side technology (runs in the users browser) and PHP is a server side technology (run on the server).

If you want to do this you have to make an ajax request to a PHP script and have that return the results you are looking for.

Why do you want to do this?