回到顶部功能Demo:
<code>
(function () {
function scroll() {
var obj = document.getElementById("scrollto");
if (!obj || obj == undefined || obj == null) {
obj = document.createElement("div");
obj.setAttribute("class", "goTop");
obj.setAttribute("id", "scrollto");
obj.setAttribute("style", "display:none;");
var objImg = document.createElement("img");
objImg.setAttribute("src", "../App_Image/Webpage/goTop.png");
objImg.setAttribute("id", "goTop");
objImg.setAttribute("onclick", "scrollTo(0,0);");
obj.appendChild(objImg);
document.body.appendChild(obj);
}
if (document.documentElement.scrollTop + document.body.scrollTop > 100) {
document.getElementById("scrollto").style.display = "block";
} else {
document.getElementById("scrollto").style.display = "none";
}
}
window.onscroll = scroll;
})();
</code>
