javascript 날짜 함수

/**

* numberComma(n)

* 숫자에 콤마 추가함(12345 --> 12,345).

*/

function numberComma(n) {

//-- 정규식

var reg = /(^[+-]?\d+)(\d{3})/;

//-- 숫자를 문자열로 변환

n += '';

while (reg.test(n))

n = n.replace(reg, '$1' + ',' + '$2');

return n;

}

 

/*yyyyMMdd 형식의 날짜 문자열을 입력 받아 연(year)을 증감한다.*/

function addYear( dateStr, year ) {

dateStr = rmNotNumChar(dateStr);

return addYearMonthDay( dateStr, year, 0, 0 );

}

 

/*yyyyMMdd 형식의 날짜 문자열을 입력 받아 일(day)을 증감한다.*/

function addDay( dateStr, day ) {

dateStr = rmNotNumChar(dateStr);

return addYearMonthDay( dateStr, 0, 0, day );

}

 

function addYearMonthDay( source, year, month, day) {

if (isNaN(source) || source.length < 8) {

return "";

}

var yyyy = source.substr(0, 4);

var mm = parseInt(source.substr(4, 2));

var dd = source.substr(6, 2);

 

var dateStr = new Date(yyyy,(mm-1),dd);

var addDay;

if (year != 0) {

//console.log('@@@ year :: '+year);

addDay = new Date( dateStr.setFullYear( dateStr.getFullYear() + year ) );

}

if (month != 0) {

//console.log('@@@ month :: '+month);

addDay = new Date( dateStr.setMonth( dateStr.getMonth() + month ) );

}

if (day != 0) {

//console.log('@@@ day :: '+day);

addDay = new Date( dateStr.setDate( dateStr.getDate() + day ) );

}

//console.log('@@@ addDay :: '+getDateYMD(addDay));

return getDateYMD(addDay);

}

 

/* 입력된 date객체를 날짜형식으로 yyyymmdd */

function getDateYMD( source ) {

var now;

if( empty(source) ){

now = new Date();

}else{

now = new Date( source );

}

 

var year = now.getFullYear();

var month = ("0" + (1 + now.getMonth())).slice(-2);

var day = ("0" + now.getDate()).slice(-2);

 

return year + month + day;

}

 

/* 입력된 str객체를 날짜형식으로 YYYY-MM-DD */

function getDateFormatYMD( source ) {

source = rmNotNumChar(source);

if (isNaN(source) || source.length < 8) {

return "";

}

var yyyy = source.substr(0, 4);

var mm = source.substr(4, 2);

var dd = source.substr(6, 2);

 

var dateStr = new Date(yyyy,(mm-1),dd);

 

var year = dateStr.getFullYear();

var month = ("0" + (1 + dateStr.getMonth())).slice(-2);

var day = ("0" + dateStr.getDate()).slice(-2);

 

return year + "-" + month + "-" + day;

}

 

/* 해당달의 마지막 날짜 구하기 */

function getlastDay( source ) {

source = source.replace(/\D/ig, "");

if (isNaN(source) || source.length < 6) {

return "";

}

var year = source.substr(0, 4);

var month = source.substr(4, 2);

var newDate = new Date(year, month, 0);

 

var newYear = newDate.getFullYear();

var newMonth = newDate.getMonth()+1;

var newDay = newDate.getDate();

//console.log(newMonth);

 

if (newMonth.toString().length < 2) newMonth = "0" + newMonth;

if (newDay.toString().length < 2) newDay = "0" + newDay;

 

return newYear.toString() + newMonth.toString() + newDay.toString();

}