Summary
最速インターフェース研究会の「実践JavaScriptリファクタリング」に触発されてDateクラスに手を加えてみた．
IEとMozilla系でgetYear(),setYear()の仕様が異なるため，
getFullYear(),setFullYear()を使うことで，年の扱いを4ケタで統一．
Source
/*
連想配列を返す
return Array
*/
Date.prototype.toHashArray = function(){
var dateArray = new Object();
dateArray["year"] = this.getFullYear();
dateArray["month"] = this.getMonth();
dateArray["date"] = this.getDate();
dateArray["day"] = this.getDay();
dateArray["hour"] = this.getHours();
dateArray["minute"] = this.getMinutes();
dateArray["second"] = this.getSeconds();
return dateArray;
}
/*
その年が閏年かどうか
return boolean
*/
Date.prototype.isLeapYear = function(){
var year = this.getFullYear();
return (((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0));
}
/*
その日が引数と同じ日付かどうか
return boolean
*/
Date.prototype.isSameDate = function(d){
var arr = this.toHashArray();
var arr2 = d.toHashArray();
return ((arr["year"] == arr2["year"]) && (arr["month"] == arr2["month"]) && (arr["date"] == arr2["date"]));
}
/*
その時間が引数と同じ時間かどうか
return boolean
*/
Date.prototype.isSameTime = function(d){
var arr = this.toHashArray();
var arr2 = d.toHashArray();
return ((arr["hour"] == arr2["hour"]) && (arr["minute"] == arr2["minute"]) && (arr["second"] == arr2["second"]));
}
/*
その時間が引数と同じ日付、同じ時間かどうか
return boolean
*/
Date.prototype.equals = function(d){
return (this.isSameDate(d) && this.isSameTime(d));
}
/*
その日が今日と同じ日付かどうか
return boolean
*/
Date.prototype.isToday = function(){
return this.isSameDate(new Date());
}
/*
時間を 00:00:00に設定
*/
Date.prototype.resetTime = function(){
this.setHours(0);
this.setMinutes(0);
this.setSeconds(0);
return;
}
/*
その月の日数を取得
return int
*/
Date.prototype.getDayNumber = function(){
var year = this.getFullYear();
var month = this.getMonth();
var dayNumber =
(month == 0 || month == 2 || month == 4 || month == 6 || month == 7 || month == 9 || month == 11) ? 31 :
(month == 3 || month == 5 || month == 8 || month == 10) ? 30 :
(this.isLeapYear()) ? 29 :
28;
return dayNumber;
}
/*
その月の週の数を取得
return int
*/
Date.prototype.getWeekNumber = function(){
var dayNumber = this.getDayNumber();
var weekOfTheDay = this.getDay();
var weekNumber = Math.ceil((weekOfTheDay + dayNumber) / 7);
return weekNumber;
}
/*
閏年を考慮して前の月のDateを返す
(3月29日,30日,31日の前の月は2月28日 or 29日)
return Date
*/
Date.prototype.getPreviousMonth = function(){
var year = this.getFullYear();
var month = this.getMonth();
var date = this.getDate();
var prevYear = year;
var prevMonth = month;
var prevDate = date;
if (month == 0){
prevMonth = 11;
prevYear--;
} else if (month == 1 || date > 28){
prevDate = (this.isLeapYear()) ? 29 : 28;
prevMonth--;
} else {
prevMonth--;
}
var retDate = new Date(prevYear,prevMonth,prevDate);
retDate.resetTime();
return retDate;
}
/*
閏年を考慮して次の月のDateを返す
(1月29日,30日,31日の次の月は2月28日 or 29日)
return Date
*/
Date.prototype.getNextMonth = function(){
var year = this.getFullYear();
var month = this.getMonth();
var date = this.getDate();
var nextYear = year;
var nextMonth = month;
var nextDate = date;
if (month == 11){
nextMonth = 0;
nextYear++;
} else if (month == 0 || date > 28){
nextDate = (this.isLeapYear()) ? 29 : 28;
nextMonth++;
} else {
nextMonth++;
}
var retDate = new Date(nextYear,nextMonth,nextDate);
retDate.resetTime();
return retDate;
}
/*
その月の最初の日付を返す。時間は00:00:00にリセット。
return Date
*/
Date.prototype.getFirstDate = function(){
var year = this.getFullYear();
var month = this.getMonth();
var retDate = new Date(year,month,1);
retDate.resetTime();
return retDate;
}
/*
読みやすい形式で日付の文字列を出力
return String
*/
Date.prototype.toReadableString = function(){
var dateArray = this.toHashArray();
var displayMonth = dateArray["month"] + 1;
var ret = '';
ret += dateArray["year"] + '/' + displayMonth + '/' + dateArray["date"];
return ret;
}
/*
読みやすい形式で日付と時刻の文字列を出力
return String;
*/
Date.prototype.toLongReadableString = function(){
var dateArray = this.toHashArray();
var day = this.getWeekOfTheDay();
var ret = '';
ret += this.toReadableString();
ret += '(' + day + ')' + dateArray["hour"] + ':' + dateArray["minute"] + ':' + dateArray["second"];
return ret;
}
/*
読みやすい曜日を返す
return String;
*/
Date.prototype.getWeekOfTheDay = function(){
var day = this.getDay();
var ret = this.weekOfTheDay[day];
return ret;
}
/*
読みやすい曜日表示の設定
引数は "7つの要素を持つArray"
return boolean;
*/
Date.prototype.setWeekOfTheDayArray = function(arr){
var state = (arr.length == 7) ? true : false;
if (state){
this.weekOfTheDay = arr;
}
return state;
}
Date.prototype.weekOfTheDay = new Array("日","月","火","水","木","金","土");
// Date.prototype.weekOfTheDay = new Array("Sun","Mon","Tue","Wed","Thu","Fri","Sat");
Reference
最速インターフェース研究会 - 2005-10-06 - 実践JavaScriptリファクタリング
http://la.ma.la/blog/diary_200510060733.htm
最速インターフェース研究会 - 2005-10-06 - 実践JavaScriptリファクタリング、その2
http://la.ma.la/blog/diary_200510062243.htm
