(Hope it is not a duplicate because I didn\'t find it when searching and googling)
I am trying to find how to detect in some fixed-height div (\'#div\') when the scroll-
Here's the code from jQuery source:
if (jQuery.isWindow(elem)) {
// As of 5/8/2012 this will yield incorrect results for Mobile Safari, but there
// isn't a whole lot we can do. See pull request at this URL for discussion:
// https://github.com/jquery/jquery/pull/764
return elem.document.documentElement["client" + name];
}
// Get document width or height
if (elem.nodeType === 9) {
doc = elem.documentElement;
// Either scroll[Width/Height] or offset[Width/Height] or client[Width/Height], whichever is greatest
// unfortunately, this causes bug #3838 in IE6/8 only, but there is currently no good, small way to fix it.
return Math.max(
elem.body["scroll" + name], doc["scroll" + name],
elem.body["offset" + name], doc["offset" + name],
doc["client" + name]);
}
So for $(window)
clientHeight is used. Which, as @Drew correctly mentioned the height of visible screen area.
For $(document)
the whole scroll height of the current page will be used.
Difference between $(window).height() and $(document).height() function.
$(window).height() function:
Ideally $(window).height() returns the pixel less height of browser window. This is always the height of current browser window. If you resize browser this value should change.
$(document).height() function: $(document).height() returns an unit-less pixel value of the height of the document being rendered.
In HTML if you dont declare DOCTYPE then all time HTML page returns $(window).height() and $(document).height() same value.
<html>
<head>
<script type='text/javascript' src='http://code.jquery.com/jquery-1.10.1.js'></script>
<script type='text/javascript'>
$(document).ready(function(){
$('#winheight').text($(window).height());
$('#docheight').text($(document).height());
});
</script>
</head>
<body>
<div id="console">
$(window).height() = <span id="winheight"></span> <br/>
$(document).height() = <span id="docheight"></span>
</div>
<p>Lorem ipsum dolor sit amet</p>
</body>
</html>
Output :
$(window).height() = 750
$(document).height() = 750
Lorem ipsum dolor sit amet
After declare DOCTYPE its returns perfect value.
<!DOCTYPE HTML>
<html>
write above code here
</html>
Output :
$(window).height() = 750
$(document).height() = 750
Lorem ipsum dolor sit amet
The height of the document is not necessarily the same as the height of the window. If you have a simple document with just a DIV and a little bit of text, the doc height will be miniscule compared to the height of the window.
In the .height() documentation:
$(window).height(); // returns height of browser viewport
$(document).height(); // returns height of HTML document
In your case it sounds like you may want the height of the document
rather than the window
. Think of it this way: The window
height is what you see, but the document
height includes everything below or above.
EXAMPLE
EDIT:
Checking for top and bottom on scroll with help from the scrollTop() method:
var bottom = $(document).height() - $(window).height();
$(document).scroll(function(){
var position = $(this).scrollTop();
if (position === bottom) {
console.log("bottom");
}else if(position === 0){
console.log("top");
} else {
console.log("scrolling");
}
});
The document height is the entire height of the whole document, even what is outside the viewable area. This could be thousands of pixels if you have a long page. The window height is just the viewable area.