Question

I have this code to make page scroll up and down,Please tell me how to make it back to scroll postion instead of down page when i click down?

<a href="javascript://" id="toDown">Down</a>
<a href="javascript://" id="toTop">Top</a>

<script type="text/javascript">
jQuery.noConflict();
$(window).scroll(function(){
    if($(window).scrollTop() > "0"){
        $('#toTop').fadeIn();
        $('#toDown').hide();
    }else if($(window).scrollTop() == "0"){
        $('#toTop').fadeOut();
        $('#toDown').fadeIn();
    }
});
$('#toTop').click(function(){
    $('html, body').animate({scrollTop:0}, 0);
    $('#toDown').fadeIn();
});
$('#toDown').click(function(){
    $('html, body').animate({$('body').height()}, 0);
    $('#toDown').fadeOut();
});
</script>

Answer 1

Add a variable to store the scroll position at the moment ‘top’ is clicked:

var iPosition = null;

If ‘top’ is clicked, save the current scroll position:

iPosition = $(window).scrollTop();

If ‘down’ is clicked, check if a scroll position has been stored; if yes, move to this position, otherwise move the the end of the document:

$('html, body').animate({scrollTop: (iPosition === null ? $('body').height() : iPosition)}, 0);

The complete source code:

var iPosition = null;                              // new
jQuery.noConflict();
$(window).scroll(function(){
    if($(window).scrollTop() > "0"){
        $('#toTop').fadeIn();
        $('#toDown').hide();
    }else if($(window).scrollTop() == "0"){
        $('#toTop').fadeOut();
        $('#toDown').fadeIn();
    }
});
$('#toTop').click(function(){
    iPosition = $(window).scrollTop();             // new
    $('html, body').animate({scrollTop:0}, 0);
    $('#toDown').fadeIn();
});
$('#toDown').click(function(){
    $('html, body').animate({scrollTop: (iPosition === null ? $('body').height() : iPosition)}, 0);   // changed
    $('#toDown').fadeOut();
});

Also see this jsfiddle.