window.onload = function() {
yourFunction(param1, param2);
};
//DOMContentLoaded It means when the DOM Objects of the document are fully loaded and seen by JavaScript, also this could have been "click", "focus"...
//function() Anonymous function, will be invoked when the event occurs.
// not work with IE8
document.addEventListener("DOMContentLoaded", function() {
you_function(...);
});