DOM HTML PARSING TIPS

dom-parsing-elements.js

$(".txtClass")                  =>  getElementsByClassName()
$("#childDiv2 .txtClass")       =>  getElementById(), then getElementsByClassName()
$("#childDiv2 > .txtClass")     =>  getElementById(), then iterate over children and check class
$("input.txtClass")             =>  getElementsByTagName(), then iterate over results and check class
$("#childDiv2 input.txtClass")  =>  getElementById(), then getElementsByTagName(), then iterate over results and check class

//Example:

$('.txtClass');
$('#childDiv2 .txtClass')
$('#childDiv2 > .txtClass')
$('input.txtClass')
$('#childDiv2 input.txtClass')

var obj = document.getElementById("childDiv");
xxx = obj.getElementsByClassName("txtClass");