How to include an external javascript file conditionally?

Question

I have this code:

<script src="http://external/js/file/url.js">
</script>

I want to do something like this-

<script>
if(2>1){
//include http://external/js/file/url.js
}
</script>

Any idea?

Answer 1

This question has been asked before in Include a Javascript File in another Javascript File. This peice of code may fit what you have been looking for

function include(filename)
{
   var head = document.getElementsByTagName('head')[0];

   var script = document.createElement('script');
   script.src = filename;
   script.type = 'text/javascript';

   head.appendChild(script)
}   

if that script does not work, i suggest you to look over and read the post above: Include a Javascript File in another Javascript File.

I hope this helps, it may not be the answer you had been looking for, but it may just help.

Answer 2

You simply load it asynchronously like

if(yourCondition==true){
var d = document,
            h = d.getElementsByTagName('head')[0],
            s = d.createElement('script');
    s.type = 'text/javascript';
    s.async = true;
    s.src = 'http://external/js/file/url.js';
    h.appendChild(s);
}

Answer 3

You could use something like:

<script type="text/javascript">

   if (condition == true) {

      document.getElementsByTagName("head")[0].innerHTML += ("<script src=\"http://external/js/file/url.js\" type=\"text/javascript\"></script>");

   }

</script>