JQuery计算滚动条长度和位置，代码如下：

javascript
复制代码 代码如下:
<script type="text/javascript">
var scrMinHeight = 1; //滚动条最小高度
var scrMaxHeight = 0; //滚动条最大高度
var scrDefualtTop = 80; //滚动条默认位置
var scrHeight = 0;
//初始化滚动条
function InitScroll() {
scrMaxHeight = $("#mainScrollContent").height(); //文本框高度
scrHeight = document.getElementById("mainScrollContent").scrollHeight; //滚动文本高度
scrHeight = parseInt((scrMaxHeight / scrHeight) * scrMaxHeight);
if (scrHeight <= scrMinHeight) { scrHeight = scrMinHeight; }
if (scrHeight >= scrMaxHeight) { $("#scrollContent").hide(); }
else {
$("#scrollContent").show();
$("#scrollContent .tiao_mid").css("height", (scrHeight - 19) + "px");
}
}

$(document).ready(function () {
$(".bod").height(($(document).height() - 80) + "px");
$("#mainScrollContent").height(($(document).height() - 125) + "px");
scrMaxHeight = ($(document).height() - 125); //滚动条最大高度
$("#scrollBody").height(($(document).height() - 125) + "px");
$("#scrollBodyBack").height(($(document).height() - 125) + "px");

InitScroll();
$("#mainScrollContent").scroll(function () {
ChangeScroll();
});
var y1 = 0;
$("#scrollContent").mousedown(function (event) {
var scrContentTop = $("#scrollContent").css("top");
y1 = event.clientY - parseInt(scrContentTop.replace("px", ""));
$("#scrollContent").mousemove(function (event) {
if ((event.clientY - y1) < scrDefualtTop) {
$("#scrollContent").css("top", scrDefualtTop + "px");
}
else if ((event.clientY - y1) > (scrDefualtTop + scrMaxHeight - scrHeight)) {
$("#scrollContent").css("top", (scrDefualtTop + scrMaxHeight - scrHeight) + "px");
}
else {
$("#scrollContent").css("top", (event.clientY - y1) + "px");
}
ChangeScrollContent();
});
}).mouseup(function () {
$("#scrollContent").unbind("mousemove");
}).mouseout(function () {
$("#scrollContent").unbind("mousemove");
});
});

//改变滚动内容位置
function ChangeScrollContent() {
var scrTop = $("#scrollContent").css("top");
var st = parseInt(scrTop.replace("px", ""));
st = ((st - scrDefualtTop) * document.getElementById("mainScrollContent").scrollHeight) / scrMaxHeight
$("#mainScrollContent").scrollTop(st); //滚动的高度
}

//改变滚动条位置
function ChangeScroll() {
var scrTop = $("#mainScrollContent").scrollTop(); //滚动的高度
scrTop = (scrTop * scrMaxHeight) / document.getElementById("mainScrollContent").scrollHeight + scrDefualtTop;
$("#scrollContent").css("top", scrTop + "px");
}
</script>

滚动区域内容DIV：
html
复制代码 代码如下:
<div class="jtc_neir" id="Div1" style="height: 100px;">
营业总收入:11.66亿元(同比增长-1.75%)
<br />
<a href="bank.aspx">dddd</a>净利润:0.19亿元(同比增长23.72%)
<br />
每股收益:0.04元
<br />
净资产收益率:1.58%
<br />
毛利率:12.22%(同比增长39.89%)
<br />
总资产:30.46亿元(同比增长-7.14%)<br />
as大苏打撒旦撒
<br />
阿斯蒂芬多个地方营业总收入:11.66亿元(同比增长-1.75%)
<br />
净利润:0.19亿元(同比增长23.72%)
<br />
每股收益:0.04元
<br />
净资产收益率:1.58%
<br />
毛利率:12.22%(同比增长39.89%)
<br />
总资产:30.46亿元(同比增长-7.14%)<br />
as大苏打撒旦撒
<br />
阿斯蒂芬多个地方营业总收入:11.66亿元(同比增长-1.75%)
<br />
净利润:0.19亿元(同比增长23.72%)
<br />
每股收益:0.04元
<br />
净资产收益率:1.58%
<br />
毛利率:12.22%(同比增长39.89%)
<br />
总资产:30.46亿元(同比增长-7.14%)<br />
as大苏打撒旦撒
<br />
阿斯蒂芬多个地方营业总收入:11.66亿元(同比增长-1.75%)
<br />
净利润:0.19亿元(同比增长23.72%)
<br />
每股收益:0.04元
<br />
净资产收益率:1.58%
<br />
毛利率:12.22%(同比增长39.89%)
<br />
总资产:30.46亿元(同比增长-7.14%)<br />
as大苏打撒旦撒
<br />
阿斯蒂芬多个地方营业总收入:11.66亿元(同比增长-1.75%)
<br />
净利润:0.19亿元(同比增长23.72%)
<br />
每股收益:0.04元
<br />
净资产收益率:1.58%
<br />
毛利率:12.22%(同比增长39.89%)
<br />
总资产:30.46亿元(同比增长-7.14%)<br />
as大苏打撒旦撒
<br />
阿斯蒂芬多个地方</div>
<div class="jtc_tiao" style="background-color: rgb(196,206,208); z-index: 2;" id="Div2">
</div>
<div class="jtc_tiao" style="background-color: rgb(222,222,222); z-index: 1; width: 16px;"
id="Div3">
</div>
<div class="jtc_tiao" id="Div4">
<div class="tiao_up">
</div>
<div class="tiao_mid">
</div>
<div class="tiao_bottom">
</div>
</div>

主要样式：
css
复制代码 代码如下:
.jtc_neir{margin-left:20px; margin-right:20px; color:#000000; font-size:12px; background:none; line-height:32px; overflow-y:scroll;overflow-x:hidden;
scrollbar-3dlight-color:rgb(222,222,222);
scrollbar-arrow-color:rgb(222,222,222);
scrollbar-base-color:rgb(222,222,222);
scrollbar-darkshadow-color:rgb(222,222,222);
scrollbar-face-color:rgb(222,222,222);
scrollbar-highlight-color:rgb(222,222,222);
scrollbar-shadow-color:rgb(222,222,222);}

.jtc_tiao{width:8px; position:absolute; top:80px; right:20px; z-index:10;}
.tiao_up{width:8px; height:10px; background:url(../images/scrollbar-3.jpg) left top no-repeat; line-height:0px; overflow:hidden;}
.tiao_mid{width:8px; background:url(../images/scrollbar-3.jpg) -39px center repeat-y; line-height:0px; overflow:hidden;}
.tiao_bottom{width:8px; height:10px; background:url(../images/scrollbar-3.jpg) -13px bottom no-repeat;font-size:0; line-height:0px; overflow:hidden;}