爲什麼瀏覽器檢測到頂部爲底部？

Question

我想在用戶點擊頁面底部時加載更多圖片。我發現很多問題解釋如何做到這一點，但我總是得到頂級的不buttom。到達底部時

$(window).on("scroll", function() { 
    var scrollHeight = $(document).height(); 
    var scrollPosition = $(window).height() + $(window).scrollTop(); 
    if ((scrollHeight - scrollPosition)/scrollHeight === 0) { 
     alert('bottom'); 
    } 
}); 

該片段應高度警惕，而是它到達頂部時警報。這發生在Chrome和Safari上。不明白爲什麼？

Answer 1

更改這個if ((scrollHeight - scrollPosition) < 1)

$(window).on("scroll", function() { 
 
    var scrollHeight = $(document).height(); 
 
    var scrollPosition = $(window).height() + $(window).scrollTop(); 
 
    if ((scrollHeight - scrollPosition) < 1) { 
 
     console.log('at bottom') 
 
    } 
 
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> 
 

 
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</div>