例子，通过程序来计算指定天数后的日期。
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<title>计算几天后的日期，js天数计算、时间计算-www.jb200.com</title>
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<center><font color=red face="隶书" size=6>记录几天后的日期</font></center>
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<table border=0 bordercolor=blue borderlight=green style="border-collapse: collapse" cellpadding="0" cellspacing="0">
<tr><td align=center><font size=5 color=red face="Arial, Helvetica, sans-serif"><strong>下面为效果显示区!</strong></font></td></tr><tr><td align=center> <script language="javascript">
<!-- Begin
function AddDays(form) {
DaysToAdd=document.form.DaysToAdd.value;
var now=new Date();
var newdate=new Date();
var newtimems=newdate.getTime()+(DaysToAdd*24*60*60*1000);
newdate.setTime(newtimems);
document.form.display.value=newdate.toLocaleString();
}
// End -->
</script>
<form name=form>
<input type=text name=DaysToAdd size=4 value=10 onFocus="this.select()" onMouseOver="this.focus()">
<input type=button value="天后的日期将是.." onClick="AddDays(this.form)" name="button">
<input type=text name="display" size=20 value="">
</form>
</td></tr>
</table></center>
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