Ajax Girl

function onContent(callback){ // (C) webreflection.blogspot.com
    // [please note that this code doesn't work]

 // private scope variable

 var IEStringToWrite =  // this is IE dedicated string

  “<script defer src=’//:’ onreadystatechange=’
  (function(element){
   
   // if readystate is complete
   if(element.readyState === “complete”)

    // call the global variable
    window.__onContent__();
  })(this);
  ‘></script>”;

 // the above string is necessary to use onreadystatechange property
 // with an undefined page. In this way IE tell us the readyState
 // of the current document

 // to call callback function IE need a global scope variable
 // this variable could call one or more callback
 // then if it’s already created we need to call the old callback
 // then this new callback
 window.__onContent__ = (function(oldCallback){
 
  // returns a function that will delete __onContent__
  // to remove multiple callbacks with different
  // events and different ways for each browser

  return function(){

   // clear __onContent__ as generic function
   window.__onContent__ = function(){};
   
   
   // checks if oldCallback isn’t null or undefined
   if(oldCallback)
    oldCallback(); // call them to preserve the right order

   callback();  // call this scope callback function
      // (sent calling onContent)
  }
 
 })(window.__onContent__); // undefined if is the first time we use __onContent__

 // __onContent__ is my function to use as callback

 // I need to add this function as event

 // Opera 9 and FireFox both support DOMContentLoaded as well as
 // addEventListener document method
 if(document.addEventListener)
  document.addEventListener(”DOMContentLoaded”, __onContent__, false);

 // if some browser supports addEventListener but doesn’t support DOMContentLoaded
 // event I don’t need to care about that because this event will never be fired

 // at the same time if Safari or KDE one day will support DOMContentLoaded
 // I prefere use this dedicated in-core
 // event instead of next trick that’s quite horrible but works with Safari,
 // KDE as Opera 8.5 and lower too

 // that’s why I don’t use an else if but an if … because the first time
 // event will be fired __onContent__
 // became an empty function … then calling them twice is not a problem

 if(
  // Safari and KDE
  /WebKit|Khtml/i.test(navigator.userAgent) ||

  // Opera less than 9
  (window.opera && parseInt(window.opera.version())&lt;9)
 )
  // runtime anonymous function
  (function(){

   // checks if document.readyState is loaded or complete
   /loaded|complete/.test(document.readyState) ?

    // then call __onContent__ , stopping internal loop
    window.__onContent__() :

    // or loops itself with the faster timeout
    setTimeout(arguments.callee, 1);
  })();

 // at this point I’ve setted the DOMContentLoaded event for every browser
 // but not for Inernet Explorer.
 else if (/MSIE/i.test(navigator.userAgent))

  // I can write dedicated string
  document.write(IEStringToWrite);
};