JS如何比较两个日期相差几天?不考虑时间


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<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>无标题文档</title>
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<script type="text/javascript"> 
var objDate1=new Date(2008,6,19,23,59,59);
var objDate2=new Date(2008,6,20,0,01,01);
var msSpan=objDate1.getTime()-objDate2.getTime();
alert("相差:"+msSpan/(24*60*60*1000)+"天");
alert("相差:"+msSpan/(60*60*1000)+"小时");
alert("相差:"+msSpan/(60*1000)+"分钟");
alert("相差:"+msSpan/(1000)+"秒");
</script>
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</body>
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