jquery计算百分比，最大值为100％

Question

简单进度条显示用户向下滚动页面特定部分的百分比，在这种情况下是文章页面（.post）的主体，当文章结尾/开头时达到100％评论已达成。

$(window).scroll(function() {
    var conheight = $('.post').height();
    var startDistance = 0;
    var scrollTop = $(document).scrollTop();
    var scrollAmount = $(window).scrollTop();
    var scrollArea = $('.commentswrapper').offset().top - $('.post').offset().top;


    // calculate the percentage the user has scrolled down the page and substract comment section
    var scrollPercent = 100 * $(window).scrollTop() / (scrollArea); 

    if (scrollTop > 0) {
        $('.progress-bar').css('width', scrollPercent +"%"  );
    } else {
        $('.progress-bar').css('width', startDistance);
    }

});

问题在于，虽然达到.post结尾时达到100％，但在滚动评论部分时它会不断扩展。

如何将scrollPercent限制为最大值100％？

Answer 1

// calculate the percentage the user has scrolled down the page and substract comment section
var scrollPercent = 100 * $(window).scrollTop() / (scrollArea);

if (scrollPercent > 100) {
    scrollPercent = 100;
}