thomasfrank.se

Easier than AJAX

• get some more javascript functions as they are needed
• or get som data fragments (JSON?) back from the server.

• you have no need to post big amounts of data back to the server
• you're not keen on running a big ajax-enabling library.

includeJS=function(url,onload,allowCache){
	url=allowCache?url:url+'&nocache='+Math.random();
	url=url.split('?').length>1?url:url.replace(/\&/,'?');
	onload=typeof onload=="function"?onload:function(){};
	var js=document.createElement('script');
	js.setAttribute('src',url);
	js.addEventListener && function(){js.addEventListener('load',onload,false)}();
	js.onreadystatechange=
		function(){this.readyState=='complete' && onload.call()};
	document.getElementsByTagName('head').item(0).appendChild(js);
};

Step by step

• if no cache is allowed - add a random number query to url to prevent caching
• make sure there is a question mark before the query variables in the url
• if onload is not a function then make it an empty function
• create a script fragment
• set the url of the script
• add an event listener for onload to the script w3c/mozilla style
• add an event listener for onload to the script ie style
• load the script by attaching it to the head section of the document.

How to use

includeJS(url,onload,allowCache)

• url - the url should be the url to the script - the script might be dynamically created by the server depending on query variables.
• onload - if you want a function to fire when the script has loaded include it here else omit this parameter or set it to false
• allowCache - if you're loading a dynamically created script don't use this parameter (or set it to false). If you're loading a big static script several times (on different pages) you might want to consider setting this to true to speed up loading a bit.

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