Executing [removed] inside retrieved by AJAX

Question

There's a div called "Content":

<div id="content"></div>

It should be filled with data from a PHP file, by AJAX, including a <script> tag. However, the script inside this tag is not being executed.

<div id="content"><!-- After AJAX loads the stuff that goes here -->
   <script type="text/javascript">
     //code
   </script>
   <!-- More stuff that DOES work here -->
</div>

Answer 1

Another thing to do is to load the page with a script such as:

<div id="content" onmouseover='myFunction();$(this).prop( 'onmouseover', null );'>
<script type="text/javascript">
function myFunction() {
  //do something
}
myFunction();
</script>
</div>

This will load the page, then run the script and remove the event handler when the function has been run. This will not run immediately after an ajax load, but if you are waiting for the user to enter the div element, this will work just fine.

PS. Requires Jquery

Answer 2

If you are injecting something that needs the script tag, you may get an uncaught syntax error and say illegal token. To avoid this, be sure to escape the forward slashes in your closing script tag(s). ie;

var output += '<\/script>';

Same goes for any closing tags, such as a form tag.

Answer 3

I had a similiar post here, addEventListener load on ajax load WITHOUT jquery

How I solved it was to insert calls to functions within my stateChange function. The page I had setup was 3 buttons that would load 3 different pages into the contentArea. Because I had to know which button was being pressed to load page 1, 2 or 3, I could easily use if/else statements to determine which page is being loaded and then which function to run. What I was trying to do was register different button listeners that would only work when the specific page was loaded because of element IDs..

so...

if (page1 is being loaded, pageload = 1) run function registerListeners1

then the same for page 2 or 3.

Answer 4

Here is the script that will evaluates all script tags in the text.

function evalJSFromHtml(html) {
  var newElement = document.createElement('div');
  newElement.innerHTML = html;

  var scripts = newElement.getElementsByTagName("script");
  for (var i = 0; i < scripts.length; ++i) {
    var script = scripts[i];
    eval(script.innerHTML);
  }
}

Just call this function after you receive your HTML from server. Be warned: using eval can be dangerous.

Demo: http://plnkr.co/edit/LA7OPkRfAtgOhwcAnLrl?p=preview

Answer 5

If you load a script block within your div via Ajax like this:

<div id="content">
    <script type="text/javascript">
    function myFunction() {
      //do something
    }
    myFunction();
    </script>
</div>

... it simply updates the DOM of your page, myFunction() does not necessarily get called.

You can use an Ajax callback method such as the one in jQuery's ajax() method to define what to execute when the request finishes.

What you are doing is different from loading a page with JavaScript included in it from the get-go (which does get executed).

An example of how to used the success callback and error callback after fetching some content:

  $.ajax({
    type: 'GET',
    url: 'response.php',
    timeout: 2000,
    success: function(data) {
      $("#content").html(data);
      myFunction();
    },
    error: function (XMLHttpRequest, textStatus, errorThrown) {
      alert("error retrieving content");
    }

Another quick and dirty way is to use eval() to execute any script code that you've inserted as DOM text if you don't want to use jQuery or other library.

Answer 6

Here is a function you can use to parse AJAX responses, especially if you use minifiedjs and want it to execute the returned Javascript or just want to parse the scripts without adding them to the DOM, it handles exception errors as well. I used this code in php4sack library and it is useful outside of the library.

function parseScript(_source) {
    var source = _source;
    var scripts = new Array();

    // Strip out tags
    while(source.toLowerCase().indexOf("<script") > -1 || source.toLowerCase().indexOf("</script") > -1) {
        var s = source.toLowerCase().indexOf("<script");
        var s_e = source.indexOf(">", s);
        var e = source.toLowerCase().indexOf("</script", s);
        var e_e = source.indexOf(">", e);

        // Add to scripts array
        scripts.push(source.substring(s_e+1, e));
        // Strip from source
        source = source.substring(0, s) + source.substring(e_e+1);
    }

    // Loop through every script collected and eval it
    for(var i=0; i<scripts.length; i++) {
        try {
          if (scripts[i] != '')
          {         
            try  {          //IE
                  execScript(scripts[i]);   
      }
      catch(ex)           //Firefox
      {
        window.eval(scripts[i]);
      }   

            }  
        }
        catch(e) {
            // do what you want here when a script fails
         // window.alert('Script failed to run - '+scripts[i]);
          if (e instanceof SyntaxError) console.log (e.message+' - '+scripts[i]);
                    }
    }
// Return the cleaned source
    return source;
 }