获取滚动条高度的方法

js 代码

//获取滚动条高度
function getScrollTop() {
    var scrollPos = 0;
    if (typeof window.pageYOffset != 'undefined') {
       scrollPos = window.pageYOffset;
    }
    else if (typeof window.document.compatMode != 'undefined' &&
       window.document.compatMode != 'BackCompat') {
       scrollPos = window.document.documentElement.scrollTop;
    }
    else if (typeof window.document.body != 'undefined') {
       scrollPos = window.document.body.scrollTop;
    }
    return scrollPos;
}