jsスクロール下部ロード

//jquery
$('.container').scroll(function(){
    var scrollTop = $(this).scrollTop();
    var scrollHeight = $(this)[0].scrollHeight;
    var clientHeight = $(this)[0].offsetHeight;
    if(scrollTop + clientHeight == scrollHeight){
		alert("       ");
    }
});
//  js
window.onscroll = function () {
    //   y     
    var scrollTop = document.documentElement.scrollTop || document.body.scrollTop;
    //       
    var clientHeight = document.documentElement.clientHeight || document.body.clientHeight;
    //            （   ）
    var scrollHeight = document.documentElement.scrollHeight || document.body.scrollHeight;
    if(scrollTop + clientHeight == scrollHeight){
             alert('      !')
         }
     }