JavaScript (with Ajax) from PHP and Output Buffering

Question

I now have a working JSON formatted file from my PHP scripts.

The next step is to have a JavaScript script to retrieve this data for sorting, filtering and displaying.

I have a working Ajax script that tests ok for pulling back data, but I need to personalize this to the individual.

Within PHP I have a Session variable called MID (Member ID).

I am trying to use PHP to build the JavaScript with the unique URL with the MID as a variable.

The following all seem to work except for replacing the midValue variable in the JavaScript text with the MID variable in the outer PHP script.

The code so far looks like this ...

    // This is a PHP file
    // Setup PHP Output Buffering to change the MID value
    session_start();
    $MID = $_SESSION['MID'];

    function callback($buffer)
    {
      return (str_replace("midValue", $MID, $buffer));
    }

    ob_start("callback");

/*

Some bits I can't show as I haven't figured out the correct Stackoverflow tags (!) ...

 - Add the usual HTML tags such as `HTML, HEAD, TITLE, BODY, SCRIPT` etc
 - Include a DIV with an ID of **json**, this will be replaced by the JSON output it
   self.
 - Enclose the params variable with the `CDATA` tags to maintain the ampersand.

*/
    params = "url=server.com/content.php?action=json&MID=" + midValue

    request = new ajaxRequest()
    request.open("POST", "getcontent.php", true)
    request.setRequestHeader("Content-type", "application/x-www-form-urlencoded")
    request.setRequestHeader("Content-length", params.length)
    request.setRequestHeader("Connection", "close")

    request.onreadystatechange = function()
    {
        if (this.readyState == 4)
        {
            if(this.status == 200)
            {
                if(this.responseText != null)
                {
                    document.getElementById('json').innerHTML = this.responseText
                }
                else alert("Ajax Error: No data recieved")
            }
            else alert("Ajax Error: " + this.statusText)
        }
    }

    request.send(params)

    function ajaxRequest()
    {
        try
        {
            var request = new XMLHttpRequest()
        }
        catch(e1)
        {
            try
            {
                request = new ActiveXObject("Msxml2.XMLHTTP")
            }
            catch(e2)
            {
                try
                {
                    request = new ActiveXObject("Microsoft.XMLHTTP")
                }
            catch(e3)
                {
                    request = false
                }
            }
    }
    return request
   }

/*
Add the closing `SCRIPT, BODY and HTML` tags here.
*/

    ob_end_flush();

And the getcontent.php file looks like this ...

       if(isset($_POST['url'])) {
            echo file_get_contents("http://" . SanitizeString($_POST['url']));
       }

       function SanitizeString($var) {
           $var = strip_tags($var);
           $var = htmlentities($var);
           return stripslashes($var);
       }

Answer 1

I think something simpler like this should work fine for you.

<?php

session_start();
$MID = $_SESSION['MID'];
?>

params = "url=server.com/content.php?action=json&MID=<?php echo $MID ?>"

request = new ajaxRequest()
request.open("POST", "getcontent.php", true)
request.setRequestHeader("Content-type", "application/x-www-form-urlencoded")
request.setRequestHeader("Content-length", params.length)
request.setRequestHeader("Connection", "close")

... // rest of javascript

<?php include 'footer.php'; // include footer code here ?>

With this method, you are just outputting the javascript and html outside of PHP so you don't need it in tags. Then you can just echo variables or include your header and footer where required.