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<title>无标题文档</title>
<style>
#parent {600px; height:20px; background:#CCC; position:relative; margin:10px auto;}
#div1 {20px; height:20px; background:red; position:absolute; left:0; top:0;}
#div2 {400px; height:300px; border:1px solid black; overflow:hidden; position:relative;}
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window.onload=function ()
{
var oDiv=document.getElementById('div1');
var oDiv2=document.getElementById('div2');
var oDiv3=document.getElementById('div3');
var oParent=document.getElementById('parent');
var disX=0;
oDiv.onmousedown=function (ev)
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var oEvent=ev||event;
disX=oEvent.clientX-oDiv.offsetLeft;
document.onmousemove=function (ev)
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var oEvent=ev||event;
var l=oEvent.clientX-disX;
if(l<0)
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l=0;
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else if(l>oParent.offsetWidth-oDiv.offsetWidth)
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l=oParent.offsetWidth-oDiv.offsetWidth;
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oDiv.style.left=l+'px';
var scale=l/(oParent.offsetWidth-oDiv.offsetWidth);
document.title=scale;
oDiv3.style.top=-scale*(oDiv3.offsetHeight-oDiv2.offsetHeight)+'px';
};
document.onmouseup=function ()
{
document.onmousemove=null;
document.onmouseup=null;
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return false; //chrome、ff、IE9
};
};
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第一部分: 入门课程、了解JavaScript - 案例+知识点,夯实基础做足准备
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