JS實現処理時間，年月日，星期的公共方法示例

Date.prototype.getWeek = function(){
  var firstDayOfYear = new Date(this.getFullYear(),0,1);
  var millOfDay = 24*60*60*1000;
  return Math.ceil((((this - firstDayOfYear) / millOfDay) + firstDayOfYear.getDay()+1)/7);
};
/*
01 October 2013-10:20:20
01 November 2013-10:20:20
01 December 2013-10:20:20
08 October 2013-01:55 pm
*/
var monthMapping = {
  "January" : "01",
  "February" : "02",
  "March" : "03",
  "April" : "04",
  "May" : "05",
  "June" : "06",
  "July" : "07",
  "August" : "08",
  "September" : "09",
  "October" : "10",
  "November" : "11",
  "December" : "12"
};
function formatAmPm() {
  var dateTimeStr = arguments[0] ;  
  var dateStr = dateTimeStr.split("-");
  if (lang.currentLang == "zh_CN" || lang.currentLang == "zh_TW"){
    var s_year = lang.getMessage('yearCn') ;
    var s_month = lang.getMessage('monthCn') ;
    var s_day = lang.getMessage('dayCn') ;
    var dateArray = dateStr[0].split(" ") ;
    var s_time = dateStr[1].split(" ")[1] == "am" ? lang.getMessage('amCn') :lang.getMessage('pmCn') ;
    var ret = dateArray[2] + s_year + monthMapping[dateArray[1]] + s_month + dateArray[0] + s_day + " " + s_time + dateStr[1].split(" ")[0] ; 
    if ( arguments.length > 1 ){
      /*admin feature ,so using en date*/
      ret = arguments[1] ? dateStr[0] : dateStr[1] ;
    }
    return ret ;
  }  
  else{
    if ( arguments.length > 1 ){
      return arguments[1] ? dateStr[0] : dateStr[1] ;      
    }
    else{
      return dateStr[0] + " " + dateStr[1] ;
    }
  }  
}
function formatDate(dateTime, pattern) {
  if(pattern == "" || pattern == null) {
    pattern = "/";
  }
  var date = new Date(dateTime);
  var year = date.getFullYear();
  var month = date.getMonth()+1;
  month = month <10 ? '0'+month : month;
  var day = date.getDate();
  day = day <10 ? '0'+day : day;
  return month + pattern + day + pattern + year;
}
function formatDateDDMMYYYY(dateTime) {
  var ymd = dateTime.split(" ")[0];
  var dateArray = ymd.split("-");
  return dateArray[2]+"."+dateArray[1]+"."+dateArray[0];
}
/**
* 
* @param dateTime YYYY-MM-DD hh:mm:ss
*/
function formatDateDDMMYY(dateTime){
  var ymd = dateTime.split(" ")[0];
  var dateArray = ymd.split("-");
  return dateArray[2]+"."+dateArray[1]+"."+dateArray[0].substring(2);
}
/**********************calculate date*****************************/
var MONTH = [
       {key:"Jan.",value:1},
       {key:"Feb.",value:2},
       {key:"Mar.",value:3},
       {key:"Apr.",value:4},
       {key:"May.",value:5},
       {key:"Jun.",value:6},
       {key:"Jul.",value:7},
       {key:"Aug.",value:8},
       {key:"Sept.",value:9},
       {key:"Oct.",value:10},
       {key:"Nov.",value:11},
       {key:"Dec.",value:12}          
       ];
var DAYS = [31,28,31,30,31,30,31,31,30,31,30,31];
function getYears(){
  var years = [];
  var date = new Date();
  var year = date.getFullYear();
  var minYear = year - 10;  
  for(var currentYear=minYear;currentYear <= year;currentYear++){
    years.push(currentYear);
  }
  return years;
};
function fillinMonthOptions(id,currentMonth){
  $("#" + id).get(0).options.length = 0;
  for(var i= 0;i<MONTH.length; i++){
    if (MONTH[i].value == currentMonth){
      $("#" + id).append("<option value="+MONTH[i].value+" selected=\"selected\">"+MONTH[i].key+"</option>");
    }
    else{
      $("#" + id).append("<option value="+MONTH[i].value+">"+MONTH[i].key+"</option>");
    }
  }
};
function fillinAllMonthOptions(monthIds,currentMonth){
  //var monthIds = ["loginMonth_1","loginMonth_2","auditMonth_1","auditMonth_2"];
  for (var i=0;i<monthIds.length;i++){
    fillinMonthOptions(monthIds[i],currentMonth);
  };  
};
function fillinYearOptions(id,years,currentYear){
  $("#" + id).get(0).options.length = 0;
  for(var i= 0;i<years.length; i++){
    if (years[i] == currentYear){
      $("#" + id).append("<option value="+years[i]+" selected=\"selected\">"+years[i]+"</option>");
    }
    else{
      $("#" + id).append("<option value="+years[i]+">"+years[i]+"</option>");
    }
  }
};
function fillinAllYearOptions(yearIds,currentYear){
  //var yearIds = ["loginYear","auditYear"];
  years = getYears();
  for(var i= 0;i<yearIds.length; i++){
    fillinYearOptions(yearIds[i],years,currentYear);
  }
};
function isLeapYear(year){
  return (year % 4 === 0) && (year % 100 !==0) || (year % 400 === 0);
}
/*get days of a month*/
function getMonthDays(year,month){
  var monthDays = DAYS[month-1];
  if (isLeapYear(year) && month == 2){
    monthDays = 29;
  }
  return monthDays;
}
function fillinDay(id,monthDays){
  $("#" + id).get(0).options.length = 0;
  for(var i=1;i<=monthDays;i++){
    $("#" + id).append("<option value="+i+">"+i+"</option>");
  }
}
function fiilinDays(year,month,dayIds){
  var monthDays = getMonthDays(year,month);
  for(var i=0;i<dayIds.length;i++){
    fillinDay(dayIds[i],monthDays);
  }
}
function getWeeksOfYear(year){
  var firstDayOfYear = new Date(year,0,1);
  var days = firstDayOfYear.getDay() + (isLeapYear(year) ? 366 : 365);
  return Math.ceil(days/7);
}
function getCurrentWeekNo(){
  var currentDate = new Date();
  var firstDay = new Date(currentDate.getFullYear(),0,1);
  var dayms = 24 * 60 * 60 * 1000;
  var numday = ((currentDate - firstDay) / dayms );
  var weeks = Math.ceil((numday + firstDay.getDay() + 1) / 7);
  return weeks;
}
function getWeekRangeOfWeek(year,weekNo){
  var tmpDate = new Date("1/20/" + year);
  var numOfDaysPastSinceLastMonday = tmpDate.getDay()-1;
  tmpDate.setDate(tmpDate.getDate() - numOfDaysPastSinceLastMonday);
  var weekNoToday = tmpDate.getWeek();
  var weeksInFuture = weekNo - weekNoToday;
  tmpDate.setDate(tmpDate.getDate() + (7 * weeksInFuture) );
  var rangeFrom = tmpDate.getDate() + "/" + MONTH[tmpDate.getMonth()].key;
  tmpDate.setDate(tmpDate.getDate() + 6);
  var rangeTo = tmpDate.getDate() + "/" + MONTH[tmpDate.getMonth()].key ;
  return weekNo + "_#_" + rangeFrom + "_#_" + rangeTo ;
}
function fillinWeek(weekId,year){
  $("#" + weekId).get(0).options.length = 0;
  var weeksOfYear = getWeeksOfYear(year);
  var weeks = [];
  for(var i=0;i<weeksOfYear;i++){
    weeks.push(getWeekRangeOfWeek(year,i+1));
  }
  for(var j=0;j<weeks.length;j++){
    var week = weeks[j].split("_#_");
    $("#" + weekId).append("<option value="+week[0]+">"+week[0] + "(" + week[1]+"-"+week[2]+")</option>");
  }
}
function fillinWeeks(year,weekIds){
  for (var i=0;i<weekIds.length;i++){
    fillinWeek(weekIds[i],year);
  }
}