js获取当前日期的前后4天

JavaScript015

js获取当前日期的前后4天,第1张

两种 一种返回Date对象，一种返回字符串。 function addDate(ds){ var d=new Date() d.setDate(d.getDate()+ds) return d } function addDays(days){ var d=new Date() d.setMilliseconds(d.getMilliseconds()+(days * 24 * 60 * 60 * 1000)) var month=d.getMonth()+1 var day = d.getDate() if(month<10){ month = "0"+month } if(day<10){ day = "0"+day } var val = d.getFullYear()+""+month+""+day return val }var d = addDate(4)var d2 = addDays(4)alert(d.getDate())alert(d2)

//dateTimeStamp是一个时间毫秒，注意时间戳是秒的形式，在这个毫秒的基础上除以1000，就是十位数的时间戳。13位数的都是时间毫秒。

function timeago(dateTimeStamp){

var minute = 1000 * 60 //把分，时，天，周，半个月，一个月用毫秒表示

var hour = minute * 60

var day = hour * 24

var week = day * 7

var halfamonth = day * 15

var month = day * 30

var now = new Date().getTime() //获取当前时间毫秒

console.log(now)

var diffValue = now - dateTimeStamp//时间差

if(diffValue <0){

return

}

var minC = diffValue/minute //计算时间差的分，时，天，周，月

var hourC = diffValue/hour

var dayC = diffValue/day

var weekC = diffValue/week

var monthC = diffValue/month

if(monthC >= 1 &&monthC <= 3){

result = " " + parseInt(monthC) + "月前"

}else if(weekC >= 1 &&weekC <= 3){

result = " " + parseInt(weekC) + "周前"

}else if(dayC >= 1 &&dayC <= 6){

result = " " + parseInt(dayC) + "天前"

}else if(hourC >= 1 &&hourC <= 23){

result = " " + parseInt(hourC) + "小时前"

}else if(minC >= 1 &&minC <= 59){

result =" " + parseInt(minC) + "分钟前"

}else if(diffValue >= 0 &&diffValue <= minute){

result = "刚刚"

}else {

var datetime = new Date()

datetime.setTime(dateTimeStamp)

var Nyear = datetime.getFullYear()

var Nmonth = datetime.getMonth() + 1 <10 ? "0" + (datetime.getMonth() + 1) : datetime.getMonth() + 1

var Ndate = datetime.getDate() <10 ? "0" + datetime.getDate() : datetime.getDate()

var Nhour = datetime.getHours() <10 ? "0" + datetime.getHours() : datetime.getHours()

var Nminute = datetime.getMinutes() <10 ? "0" + datetime.getMinutes() : datetime.getMinutes()

var Nsecond = datetime.getSeconds() <10 ? "0" + datetime.getSeconds() : datetime.getSeconds()

result = Nyear + "-" + Nmonth + "-" + Ndate

}

return result

}

提供一个思路,自己尝试写代码.如果不会写再追问:

先把自己想要的时间换算成秒=S,比如定位到一分钟前则为60秒,然后获取当前时间时间戳减去S,再将得出的结果转化为北京时间即可