js滑动加载

/* 发帖按钮控制与滑动加载*/


$(function() {
var session = window.sessionStorage;
var i = 5;
session.setItem("key", i);
var intJ = parseInt(session.getItem("key"));
console.log(intJ);
var obj = document.getElementById("cssComment");
for ( var J = 0; J <= obj.childNodes.length / 2; J++) {
if (J > intJ) {
for ( var J; J <= obj.childNodes.length; J++) {


$("#cssSingleComment" + J).hide();
}
}
}
var p = $(".sendPostImg");
var c = $(".cssComment");
$(window).scroll(function() {
var offestDis = $(document).scrollTop();
p.css({
top : offestDis + 535 + "px"
});
c.css({
height : offestDis + 600 + "px"
});
var scrollTop = $(this).scrollTop();
var scrollHeight = $(document).height();
var windowHeight = $(this).height();
if (scrollTop + windowHeight == scrollHeight) {
var i = session.getItem("key");
i = parseInt(i);
i = i + 5;
session.setItem("key", i);
var intI = parseInt(session.getItem("key"));
if (i > intI - 6 && i <=intI) {
for ( var i = intI - 6; i <= intI; i++) {
$("#cssSingleComment" + i).show();
}
} 
} 


});


});