var td=new Date()
var y=td.getFullYear()
var m=td.getMonth()+1
var d=td.getDate()
var nd=new Date(prompt("请输入日期（格式为yyyy/mm/dd）",y+"/"+m+"/"+d))
nd.setDate(nd.getDate()+1)
alert("下一天是"+nd.toLocaleDateString())
</script>
<script>document.writeln('练习6：<br>'+' 输入年份、月份，显示当月的天数'+'<br>')
var year= parseInt(prompt('练习6\n请输入一个年份'))
var month= parseInt(prompt('练习6\n请输入一个月份'))
document.writeln('您输入了'+year+'年'+'<br>')
document.writeln('您输入了'+month+'月'+'<br>')
switch(month)
{
case 1:
case 3:
case 5:
case 7:
case 8:
case 10:
case 12:
document.writeln('您输入的'+month+'月'+'有31天')
break
case 4:
case 6:
case 9:
case 11:
document.writeln('您输入的'+month+'月'+'有30天')
break
case 2:
if(year%4===0&&year%100!==0||year%400===0)
{
document.writeln('您输入的'+month+'月'+'有29天')
}else
{
document.writeln('您输入的'+month+'月'+'有28天')
}
// (years%4===0&&years%100!==0||years%400===0)?
// document.writeln('本月有29天'):
// document.writeln('本月有28天')
break
ddefault :
document.writeln('亲，您的输入不正确'+'您输入的是'+month+'月')
break
}
</script>
<script type="text/javascript">window.onload = function (){
var mydate = new Date()
alert(addDay(mydate, 5))//加 5 天
}
function addDay(dt, day){
var allseconds = dt.getTime()//参数时间的毫秒数
var ds = 24*60*60*1000//一天的毫秒数
var nds = ds * day//N天的毫秒数
var t = new Date(Math.abs(allseconds) + nds)
//return t//返回时间对象
var yyyy = t.getFullYear()
var M = t.getMonth() + 1//值范围0-11
var dd = t.getDate() //值范围1-31
var h = t.getHours()
var m = t.getMinutes()
var s = t.getSeconds()
return yyyy + "-" + M + "-" + dd + " " + h + ":" + m + ":" + s
}
</script>
