js date-formatter

//这是一个用来格式化时间的扩展，只需要引用进来就可以，本案例是一个reactJS的写法
'use strict';
//this module is used to forma date
//if you want to extend more,you can add your code here
module.exports = function(module) {
String.repeat = function(chr, count) {
var str = "";
for(var i = 0; i < count; i++) {
str += chr;
}
return str;
};

String.prototype.padL = function(width, pad) {
//not pad to left when width is 0
if (!width || width < 1) {
return this;
}
//if pad string is empty, pad a empty string here;
if (!pad) {
pad=" ";
}
var length = width - this.length;
if (length < 1) {
return this.substr(0,width);
}
return (String.repeat(pad,length) + this).substr(0,width);
};

String.prototype.padR = function(width, pad){
//not pad to right when width is 0
if (!width || width<1) {
return this;
}
//if pad string is empty, pad a empty string here;
if (!pad) {
pad=" ";
}
var length = width - this.length;
if (length < 1) {
this.substr(0,width);
}
return (this + String.repeat(pad,length)).substr(0,width);
};

Date.prototype.formatDate = function(format){
var date = this;
//set a default formatter string
if (!format) {
format= "MM/dd/yyyy";
}
var month = date.getMonth() + 1;
var year = date.getFullYear();
format = format.replace("MM",month.toString().padL(2,"0"));

if (format.indexOf("yyyy") > -1) {
format = format.replace("yyyy",year.toString());
} else if (format.indexOf("yy") > -1) {
format = format.replace("yy",year.toString().substr(2,2));
}
format = format.replace("dd",date.getDate().toString().padL(2,"0"));
var hours = date.getHours();
if (format.indexOf("t") > -1) {
if (hours > 11) {
format = format.replace("t","pm");
} else {
format = format.replace("t","am");
}
}
if (format.indexOf("HH") > -1) {
format = format.replace("HH",hours.toString().padL(2,"0"));
}
if (format.indexOf("hh") > -1) {
if (hours > 12) hours - 12;
if (hours == 0) hours = 12;
format = format.replace("hh",hours.toString().padL(2,"0"));
}
if (format.indexOf("mm") > -1) {
format = format.replace("mm",date.getMinutes().toString().padL(2,"0"));
}

if (format.indexOf("ss") >
4000
-1) {
format = format.replace("ss",date.getSeconds().toString().padL(2,"0"));
}
return format;
};
};

//使用
var newTimer = new Date(new Date().getTime()).formatDate('yyyy-MM-dd HH:mm');

module.exports = function (timer, fmt = 'YYYY-MM-DD HH:mm:ss') {
var date = new Date(timer)
var o = {
'M+': date.getMonth() + 1,
'D+': date.getDate(),
'h+': date.getHours() % 12 === 0 ? 12 : date.getHours() % 12,
'H+': date.getHours(),
'm+': date.getMinutes(),
's+': date.getSeconds(),
'q+': Math.floor((date.getMonth() + 3) / 3),
'S': date.getMilliseconds()
}
var week = {
'0': '\u65e5',
'1': '\u4e00',
'2': '\u4e8c',
'3': '\u4e09',
'4': '\u56db',
'5': '\u4e94',
'6': '\u516d'
}
if (/(Y+)/.test(fmt)) {
fmt = fmt.replace(RegExp.$1, (date.getFullYear() + '').substr(4 - RegExp.$1.length))
}
if (/(E+)/.test(fmt)) {
fmt = fmt.replace(RegExp.$1, ((RegExp.$1.length > 1) ? (RegExp.$1.length > 2 ? '\u661f\u671f' : '\u5468') : '') + week[date.getDay() + ''])
}
for (var k in o) {
if (new RegExp('(' + k + ')').test(fmt)) {
fmt = fmt.replace(RegExp.$1, (RegExp.$1.length === 1) ? (o[k]) : (('00' + o[k]).substr(('' + o[k]).length)))
}
}
return fmt
}