js 时间处理函数 获取今天的前几天和后几天的任意一天

 

var now = new Date();

let today = now.getFullYear() + '-' + (now.getMonth() + 1) + '-' + now.getDate();//2018-3-27

var nowDayOfWeek = now.getDay();

console.log(nowDayOfWeek )

dateObject.getDay()
返回值
dateObject 所指的星期中的某一天，使用本地时间。返回值是 0（周日） 到 6（周六） 之间的一个整数。

 

 

that.getWeek(0)   //今天

 

//----------------------------------------------------------------------------------------------

onLoad() {

let _this = this;

let spjlNo = this.data.spjlNo;

let that = this;

let user = wx.getStorageSync('user');

promiseHandle(wx.getSystemInfo).then((data) => {

_this.setData({

updatePanelTop: data.windowHeight

});

});

changeDate.call(this);

let date = new Date();

let todaytime = date.getFullYear() + '-' + (date.getMonth() + 1) + '-' + date.getDate();

this.setData({

todaytime: todaytime,

cheToday: todaytime,

dayIndex:date.getDate()

})

// 服药记录

that.sleepRq(todaytime);

that.foodRq(todaytime);

let now = new Date();

 

let today = now.getFullYear() + '-' + (now.getMonth() + 1) + '-' + now.getDate();

let nowDayOfWeek = now.getDay();

console.log(today)

this.selectFn(nowDayOfWeek, today)

},

selectFn: function (n, toady) {

let that=this;

let weekdays = this.data.weekdays;

if (n != 0) {

weekdays[n - 1] = toady;

} else {

weekdays[weekdays.length - 1] = toady

}

// console.log(weekdays)

// console.log(n)

for (let i = 0; i < weekdays.length; i++) {

if (weekdays[i] == '') {

// console.log(i)

if (i > n - 1) {

weekdays[i] = this.getWeek(i - (n-1)+1 )

} else {

weekdays[i] = this.getWeek(i-(n-1)+1 )

}

}

if (i >= weekdays.length - 1) {

setTimeout(function () {

 

that.chuLiday(weekdays);

}, 300);

}

}

},

chuLiday: function (weekdays){

let that=this;

// var arr = str.split(",");

for (let key in weekdays ){

weekdays[key] = weekdays[key].split("-");

}

// console.log(weekdays)

that.setData({

weekdays: weekdays

})

},

getWeek: function (i) {

var now = new Date();

var firstDay = new Date(now - (now.getDay() - 2) * 86400000);

firstDay.setDate(firstDay.getDate() + i);

let mon = Number(firstDay.getMonth()) + 1;

return now.getFullYear() + "-" + mon + "-" + firstDay.getDate();

},