How to use onload on DIV elements?

Question

I am set some similar functions for different pages on a website. So these functions are in the same file. When the JS file is loaded the functions $(function() { /*function1*/ }); and $(function() { /*function2*/ }); are executed. However, the elements which I pick up via jQuery (Ex.: $('.elem').val();) will not exist as they are on another page.

How do I execute a function only when a determining element is loaded?

Answer 1

depending on the operations you want to do with the (s) element(s), the ideal is to use $.each so that you can reference each of them with $(this) or with the variables of the parameters.

Ex:

$(".layout_cron").each(function(index, element) {
    if ($(this).data("elemento")) elemento = $(this).data("elemento"); else elemento = "#" + $(this).attr("id");
    cronometro_regressivo($(this).data("agora"), $(this).data("fim"), elemento);
});

HTML

<div id="header_banner_cron" class="layout_cron" data-agora="1407032260" data-fim="1407553140" style="position:absolute;left:197px;top:0px;"></div>

Answer 2

One way to know if an element exists with jQuery is to use the length property. $('.elem').length tells you how many elements there are on the page that match the selector .elem.

if( $('.elem').length > 0 ){
   //tem nós da classe elem no documento
}else{
   //nao tem
}