js中日期的加减法

今天就算对JS中日期的加减法做个总结，一共两步

第一步，引入date.format.js，这个JS的作用是将日期转为指定的格式，代码如下

rush:js;"> var dateFormat = function () { var token = /d{1,4}|m{1,4}|yy(?:yy)?|([HhMsTt])\1?|[LloSZ]|"[^"]*"|'[^']*'/g,timezone = /\b(?:[PMCEA][SDP]T|(?:Pacific|Mountain|Central|Eastern|Atlantic) (?:Standard|Daylight|Prevailing) Time|(?:GMT|UTC)(?:[-+]\d{4})?)\b/g,timezoneClip = /[^-+\dA-Z]/g,pad = function (val,len) { val = String(val); len = len || 2; while (val.length < len) val = "0" + val; return val; };

// Regexes and supporting functions are cached through closure
return function (date,mask,utc) {
var dF = dateFormat;

// You can't provide utc if you skip other args (use the "UTC:" mask prefix)
if (arguments.length == 1 && Object.prototype.toString.call(date) == "[object String]" && !/\d/.test(date)) {
  mask = date;
  date = undefined;
}

// Passing date through Date applies Date.parse,if necessary
date = date ? new Date(date) : new Date;
if (isNaN(date)) throw SyntaxError("invalid date");

mask = String(dF.masks[mask] || mask || dF.masks["default"]);

// Allow setting the utc argument via the mask
if (mask.slice(0,4) == "UTC:") {
  mask = mask.slice(4);
  utc = true;
}

var  _ = utc ? "getUTC" : "get",d = date[_ + "Date"](),D = date[_ + "Day"](),m = date[_ + "Month"](),y = date[_ + "FullYear"](),H = date[_ + "Hours"](),M = date[_ + "Minutes"](),s = date[_ + "Seconds"](),L = date[_ + "Milliseconds"](),o = utc ? 0 : date.getTimezoneOffset(),flags = {
    d:  d,dd:  pad(d),ddd: dF.i18n.dayNames[D],dddd: dF.i18n.dayNames[D + 7],m:  m + 1,mm:  pad(m + 1),mmm: dF.i18n.monthNames[m],mmmm: dF.i18n.monthNames[m + 12],yy:  String(y).slice(2),yyyy: y,h:  H % 12 || 12,hh:  pad(H % 12 || 12),H:  H,HH:  pad(H),M:  M,MM:  pad(M),s:  s,ss:  pad(s),l:  pad(L,3),L:  pad(L > 99 ? Math.round(L / 10) : L),t:  H < 12 ? "a" : "p",tt:  H < 12 ? "am" : "pm",T:  H < 12 ? "A" : "P",TT:  H < 12 ? "AM" : "PM",Z:  utc ? "UTC" : (String(date).match(timezone) || [""]).pop().replace(timezoneClip,""),o:  (o > 0 ? "-" : "+") + pad(Math.floor(Math.abs(o) / 60) * 100 + Math.abs(o) % 60,4),S:  ["th","st","nd","rd"][d % 10 > 3 ? 0 : (d % 100 - d % 10 != 10) * d % 10]
  };

return mask.replace(token,function ($0) {
  return $0 in flags ? flags[$0] : $0.slice(1,$0.length - 1);
});

};
}();

// Some common format strings
dateFormat.masks = {
"default": "ddd mmm dd yyyy HH:MM:ss",shortDate: "m/d/yy",mediumDate: "mmm d,yyyy",longDate: "mmmm d,fullDate: "dddd,mmmm d,shortTime: "h:MM TT",mediumTime: "h:MM:ss TT",longTime: "h:MM:ss TT Z",isoDate: "yyyy-mm-dd",isoTime: "HH:MM:ss",isoDateTime: "yyyy-mm-dd'T'HH:MM:ss",isoUtcDateTime: "UTC:yyyy-mm-dd'T'HH:MM:ss'Z'"
};

// Internationalization strings
dateFormat.i18n = {
dayNames: [
"Sun","Mon","Tue","Wed","Thu","Fri","Sat","Sunday","Monday","Tuesday","Wednesday","Thursday","Friday","Saturday"
],monthNames: [
"Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec","January","February","march","April","June","July","August","September","October","November","December"
]
};

// For convenience...
Date.prototype.format = function (mask,utc) {
return dateFormat(this,utc);
};

第二步，将时间转换为毫秒进行加减计算，然后再用上面的js的转为指定的日期

rush:js;"> var NowDate = new Date(); //加法操作 var ysDate = new Date(NowDate.getTime()-30*24*60*60*1000).format('yyyy-mm-dd'); //减法操作 var yeDate = new Date(NowDate.getTime()-24*60*60*1000).format('yyyy-m-d');

通过以上两步就实现了，JS中日期的加减法，怎么样简单吧！快去试试！

以上所述就是本文的全部内容了，希望大家能够喜欢。

js中日期的加减法

相关推荐