화면이 길어질경우 버튼을 클릭하여 상단으로 올라가게 하고싶을경우.

JAVASCRIPT

function go_top(orix, oriy, desx, desy) {

    var Timer;

    if (document.body.scrollTop == 0) {

        var winHeight = document.documentElement.scrollTop;

    } else {

        var winHeight = document.body.scrollTop;

    }

    if (Timer) clearTimeout(Timer);

    startx = 0;

    starty = winHeight;

    if (!orix || orix < 0) orix = 0;

    if (!oriy || oriy < 0) oriy = 0;

    var speed = 7;

    if (!desx) desx = 0 + startx;

    if (!desy) desy = 0 + starty;

    desx += (orix - startx) / speed;

    if (desx < 0) desx = 0;

    desy += (oriy - starty) / speed;

    if (desy < 0) desy = 0;

    var posX = Math.ceil(desx);

    var posY = Math.ceil(desy);

    window.scrollTo(posX, posY);

    if ((Math.floor(Math.abs(startx - orix)) < 1) && (Math.floor(Math.abs(starty - oriy)) < 1)) {

        clearTimeout(Timer);

        window.scroll(orix, oriy);

    } else if (posX != orix || posY != oriy) {

        Timer = setTimeout("go_top(" + orix + "," + oriy + "," + desx + "," + desy + ")", 15);

    } else {

        clearTimeout(Timer);

    }

}

HTML

<a style="z-index:9999;display:scroll;position:fixed;bottom:8px;right:10px;" onclick="go_top();" title="top"><img src="./top.png" border=0 style="cursor:pointer" /></a> 

IMAGE 파일.