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Executing <script> elements inserted with .innerHTML

Answer 1

A:

You may take a look at this post. The code might look like this:

var actualDivToBeUpdated = document.getElementById('test');
var div = document.createElement('div');
div.innerHTML = '<script type="text/javascript">alert("test");<\/script>';
var children = div.childNodes;
actualDivToBeUpdated.innerHTML = '';
for(var i = 0; i < children.length; i++) {
    actualDivToBeUpdated.appendChild(children[i]);
}

Darin Dimitrov 2010-04-07 11:58:33

Answer 2

A:

You should not use the innerHTML property but rather the appendChild method of the Node: a node in a document tree [HTML DOM]. This way you are able to later call your injected code.

Make sure that you understand that node.innerHTMl != (IS NO THE SAME AS) node.appendChild. You might want to spend some time on the Javascript Client Reference for more details and the DOM...hope the following helps.

Sample injection works:

<html>
<head>
<title>test</title>
<script language="javascript" type="text/javascript">
    function doOnLoad(){
        addScript('inject',"function foo(){ alert('injected'); }");
    }


    function addScript(inject,code){
        var _in = document.getElementById('inject');
        var scriptNode = document.createElement('script');
        scriptNode.innerHTML = code;
        _in.appendChild(scriptNode);
    }

</script>
</head>
<body onload="doOnLoad();">
    <div id="header">some content</div>
    <div id="inject"></div>
    <input type="button" onclick="foo(); return false;" value="Test Injected" />
</body>
</html>

regards,

andreas 2010-04-07 14:06:51

Answer 3

+1 A:

Try this snippet:

function stripAndExecuteScript(text) {
    var scripts = '';
    var cleaned = text.replace(/<script[^>]*>([\s\S]*?)<\/script>/gi, function(){
        scripts += arguments[1] + '\n';
        return '';
    });

    if (window.execScript){
        window.execScript(scripts);
    } else {
        var head = document.getElementsByTagName('head')[0];
        var scriptElement = document.createElement('script');
        scriptElement.setAttribute('type', 'text/javascript');
        scriptElement.innerText = scripts;
        head.appendChild(scriptElement);
        head.removeChild(scriptElement);
    }
    return cleaned;
};


var scriptString = '<scrip' + 't + type="text/javascript">alert(\'test\');</scr' + 'ipt><strong>test</strong>';
document.getElementById('element').innerHTML = stripAndExecuteScript(scriptString);

fantactuka 2010-06-03 14:52:50

Answer 4

+2 A:

The OP's script doesn't work in IE 7. With help from SO, here's a script that does:

exec_body_scripts: function(body_el) {
  // Finds and executes scripts in a newly added element's body.
  // Needed since innerHTML does not run scripts.
  //
  // Argument body_el is an element in the dom.

  function nodeName(elem, name) {
    return elem.nodeName && elem.nodeName.toUpperCase() ===
              name.toUpperCase();
  };

  function evalScript(elem) {
    var data = (elem.text || elem.textContent || elem.innerHTML || "" ),
        head = document.getElementsByTagName("head")[0] ||
                  document.documentElement,
        script = document.createElement("script");

    script.type = "text/javascript";
    try {
      // doesn't work on ie...
      script.appendChild(document.createTextNode(data));      
    } catch(e) {
      // IE has funky script nodes
      script.text = data;
    }

    head.insertBefore(script, head.firstChild);
    head.removeChild(script);
  };

  // main section of function
  var scripts = [],
      script,
      children_nodes = body_el.childNodes,
      child,
      i;

  for (i = 0; children_nodes[i]; i++) {
    child = children_nodes[i];
    if (nodeName(child, "script" ) &&
      (!child.type || child.type.toLowerCase() === "text/javascript")) {
          scripts.push(child);
      }
  }

  for (i = 0; scripts[i]; i++) {
    script = scripts[i];
    if (script.parentNode) {script.parentNode.removeChild(script);}
    evalScript(scripts[i]);
  }
};

Larry K 2010-07-14 20:48:56

Answer 5

A:

@phidah... Here is a very interesting solution to your problem: http://24ways.org/2005/have-your-dom-and-script-it-too

So it would look like this instead:

<img src="empty.gif" onload="alert('test');this.parentNode.removeChild(this);" />

2010-09-15 03:01:00

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Executing <script> elements inserted with .innerHTML

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