比如：
str1 = "2002-01-20"
str2 = "2002-10-11"
怎样用javaScript计算出str1与str2之间相差的天数？
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1<html>
2<head>
3<meta content="text/html; charset=utf-8" http-equiv="Content-Type"/>
4<title></title>
5</head>
6<body>
7<button onclick="btnCount_Click()">计算相差天数</button>
8<script language="JavaScript">
9
10function btnCount_Click(){
11s1 = "2002-1-10"
12s2 = "2002-10-1"
13alert(DateDiff(s1,s2))
14}
15
16//计算天数差的函数，通用
17function DateDiff(sDate1, sDate2){ //sDate1和sDate2是2002-12-18格式
18var aDate, oDate1, oDate2, iDays
19aDate = sDate1.split("-")
20oDate1 = new Date(aDate[1] + '-' + aDate[2] + '-' + aDate[0]) //转换为12-18-2002格式
21aDate = sDate2.split("-")
22oDate2 = new Date(aDate[1] + '-' + aDate[2] + '-' + aDate[0])
23iDays = parseInt(Math.abs(oDate1 - oDate2) / 1000 / 60 / 60 /24) //把相差的毫秒数转换为天数
24return iDays
25}
26
27</script>
28</body>
29</html>