How to use PHP to send javascript

Question

I posted a more specific question on this yesterday, but I think my problem is more basic than what I initially asked.

I am trying to use PHP to set a setTimeout() with a wait variable from a database, but any script I echo doesn't work, even if it involves no PHP manipulation. Take a look below.

Here is the ajax call

function loadContent()
{
    $.ajax(
    {
        url: "controller/loadContent.php",
        cache: false,
        success: function(html)
        {
            $("#contentWindow").html(html);
        }
    });
}
// Initial Load
loadContent();

And here is the PHP it receives.

        echo '<h1>Upload content to start the show</h1>';

        echo '<script>
        setTimeout(loadContent, 4000);
        </script>';

The is showing, so I believe the ajax and the PHP is working properly. The script works properly when I place it inside the javascript file, but the script won't run when it's echoed to the page.

My problem is the javascript I echo doesn't run. How can I use PHP to send javascript to the user? Why is what I wrote not functioning?

UPDATE: I realized that when I echo script, it echoed to the middle of the body and technically is above where the script file is loaded on the bottom of the body. Can I echo to the bottom of the body?

Not very clear what is your problem, but there is difference between .text(someCode) and .html(someCode). You must evaluate code to run it (first one will not evaluate, while second one do evaluate) — Justinas
– Justinas, Commented Nov 20, 2014 at 14:32
My problem is the javascript I echo in the PHP isn't running. I'm guessing you're referring to the success. The .html(html). Should I see if using .text(html) works? — Goose
– Goose, Commented Nov 20, 2014 at 14:35
Because after I get it working, I'll be using PHP to manipulate the setTimeout duration. Also, I want to understand the problem. — Goose
– Goose, Commented Nov 20, 2014 at 14:44
I had this very same problem a while ago and I solved it by performing a check over the echo, but sadly this project is saved on my homePC so I cant see how I solved it back then again. So I'll try to post my solution as soon as I get home, which is in little over 2 hours, but I can tell you it was pretty efficient. — kpp
– kpp, Commented Nov 20, 2014 at 14:48

Hackerman · Accepted Answer · 2014-11-20 15:53:09Z

2

Here is a workaround:

function loadContent()
{
$.ajax(
{
    url: "controller/loadContent.php",
    cache: false,
    success: function(html)
    {
        var myArray = html.split("|");
        var message = myArray[0];
        var counter = parseInt(myArray[1]); //Minor fix
        $("#contentWindow").html(message);
        startCounter(counter);
    }
});
}

function startCounter(counter){
    //counter as the value of 1000 milliseconds are equal to 1 second
    setTimeout(loadContent, counter);
}

PHP File

$refreshTimer = 1000; //This is a test
echo "Upload content to start the show|".$refreshTimer; //The message and the counter

edited Nov 20, 2014 at 15:53

answered Nov 20, 2014 at 14:42

Hackerman

12.3k2 gold badges37 silver badges47 bronze badges

Sign up to request clarification or add additional context in comments.

12 Comments

Goose Over a year ago

It seems to be working. I'll keep implementing and testing it and will let you know. Can you explain what I was doing wrong, and why this works?

Goose Over a year ago

I'm using | instead of / to split so I can keep using tags in my HTML. I recommend changing this in your HTML.

Hackerman Over a year ago

When you are returning a string with javascript code from php via ajax, you need to evaluate this code on the client in order to make it work, but, the use of eval is considered a bad practice,so this is a better workaround than using eval

Goose Over a year ago

I'm trying to replace the number with a php variable like so. echo '|'.$refreshTimer.''; Instead, it's setting the counter to one second. Do I need to parse the variable in some way?

Goose Over a year ago

Nope, counter is still set to 1 second. The $refreshTimer variable is still echoing the correct amount of time (60000). Do I need to parse it to a Int, and if so, do I do so in PHP or javascript?

|

thinkinglemur · Accepted Answer · 2014-11-20 15:38:51Z

0

If you return just the script portion in your php file you can set the dataType in the .ajax call to 'script' and it will execute the returned javascript (http://api.jquery.com/jquery.ajax/)

So:

function loadContent()
{
   $.ajax(
   {
       url: "controller/loadContent.php",
       cache: false,
       dataType: 'script',
       success: function(html)
       {
           $("#contentWindow").html(html);
       }
  });
}

// Initial Load loadContent();

Then in your PHP:

echo 'setTimeout(loadContent, 4000);';

edited Nov 20, 2014 at 15:38

answered Nov 20, 2014 at 14:52

thinkinglemur

463 bronze badges

3 Comments

Goose Over a year ago

I tried this code, and it never loaded the content. The rest of the javascript on the page worked, so it's valid javascript. Not sure why it didn't load $contentWindow. Let me know if you can correct it, because your solution seems much more straight forward and drier.

Goose Over a year ago

After playing with it, it seems dataType: 'script', is causing the trouble.

thinkinglemur Over a year ago

Try removing the <script> tag in your PHP file.

Collectives™ on Stack Overflow

How to use PHP to send javascript

2 Answers 2

12 Comments

3 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

12 Comments

3 Comments

Your Answer

Sign up or log in

Post as a guest

Related