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這篇文章介紹了純文字版返回頂端的js代碼，有需要的朋友可以參考一下

復制代碼 代碼如下:

<script language="javascript">

var goto_top_type = -1;

var goto_top_itv = 0;

function goto_top_timer() {

var y = goto_top_type == 1 ? document.documentElement.scrollTop

: document.body.scrollTop;

var moveby = 15;

y -= Math.ceil(y * moveby / 100);

if (y < 0) {

y = 0;

}

if (goto_top_type == 1) {

document.documentElement.scrollTop = y;

} else {

document.body.scrollTop = y;

}

if (y == 0) {

clearInterval(goto_top_itv);

goto_top_itv = 0;

}

}

function goto_top() {

if (goto_top_itv == 0) {

if (document.documentElement && document.documentElement.scrollTop) {

goto_top_type = 1;

} else if (document.body && document.body.scrollTop) {

goto_top_type = 2;

} else {

goto_top_type = 0;

}

if (goto_top_type > 0) {

goto_top_itv = setInterval('goto_top_timer()', 50);

}

}

}

</script>

<a href="javascript:void(0)" onclick="goto_top()">【返回頂部】</a>

更多信息請查看IT技術專欄