Holiday function JavaScript

Holiday Calculator Function - JavaScript
(A free script from MRE Software)

I needed a JavaScript function that would tell me whether the stock market was open or closed for a holiday so a page could decide whether to run a stock ticker or financial news ticker. I wound up piecing together two nice code snippets and adding some code of my own to create a function. This was originally based on a function to return Federal Holidays. I added the Easter (Good Friday) algorithm and the block which moves some holidays to Friday-before and Monday-after if the holiday occurs on the weekend.

I did NOT write 90% of this code so I certainly don't claim credit for doing much more than assembling it. The two main functions were both found as snippets on coding websites and neither listed an original author. That said, feel free to use, modify, and distribute this as you wish. Note that I have commented out a few Federal holidays that are not stock market holidays. The user can easily re-enable these and modify, delete, or add new ones.

Call this function by passing a valid date to it. It returns the holiday name if the date is a holiday or false if not.
When you loaded the page this function was called and returned:

To download this script as a file

USE AT YOUR OWN RISK!

function check_holiday (dt_date) { // check for market holidays // dt_date = new Date("2017-04-14T12:01:00Z"); // for testing purposes // check simple dates (month/date - no leading zeroes) var n_date = dt_date.getDate(); var n_month = dt_date.getMonth() + 1; var s_date1 = n_month + '/' + n_date; var s_year = dt_date.getFullYear(); var s_day = dt_date.getDay(); // day of the week 0-6 switch(s_date1){ case '1/1': return "New Year's"; case '6/19': return "Juneteenth"; case '7/4': return "Independence Day"; case '12/25': return "Christmas"; case GoodFriday(s_year): return "Good Friday"; } // special cases - friday before or monday after weekend holiday if (s_day == 5){ // Friday before switch(s_date1){ case '12/31': return "New Year's"; case '6/18': return "Juneteenth"; case '7/3': return "Independence Day"; case '12/24': return "Christmas"; } } if (s_day == 1){ // Monday after switch(s_date1){ case '1/2': return "New Year's"; case '6/20': return "Juneteenth"; case '7/5': return "Independence Day"; case '12/26': return "Christmas"; } } // weekday from beginning of the month (month/num/day) var n_wday = dt_date.getDay(); var n_wnum = Math.floor((n_date - 1) / 7) + 1; var s_date2 = n_month + '/' + n_wnum + '/' + n_wday; switch(s_date2){ case '1/3/1': return "ML King Birthday"; case '2/3/1': return "President's Day"; case '9/1/1': return "Labor Day"; case '11/4/4': return "Thanksgiving"; } // weekday number from end of the month (month/num/day) var dt_temp = new Date (dt_date); dt_temp.setDate(1); dt_temp.setMonth(dt_temp.getMonth() + 1); dt_temp.setDate(dt_temp.getDate() - 1); n_wnum = Math.floor((dt_temp.getDate() - n_date) / 7) + 1; var s_date3 = n_month + '/' + n_wnum + '/' + n_wday; if ( s_date3 == '5/1/1' // Memorial Day, last Monday in May ) return 'Memorial Day'; // misc complex dates // if (s_date1 == '1/20' && (((dt_date.getFullYear() - 1937) % 4) == 0) // Inauguration Day, January 20th every four years, starting in 1937. // ) return 'Inauguration Day'; // if (n_month == 11 && n_date >= 2 && n_date < 9 && n_wday == 2 // Election Day, Tuesday on or after November 2. // ) return 'Election Day'; return false; } function GoodFriday(Y) { // calculates Easter Sunday and subtracts 2 days var C = Math.floor(Y/100); var N = Y - 19*Math.floor(Y/19); var K = Math.floor((C - 17)/25); var I = C - Math.floor(C/4) - Math.floor((C - K)/3) + 19*N + 15; I = I - 30*Math.floor((I/30)); I = I - Math.floor(I/28)*(1 - Math.floor(I/28)*Math.floor(29/(I + 1))*Math.floor((21 - N)/11)); var J = Y + Math.floor(Y/4) + I + 2 - C + Math.floor(C/4); J = J - 7*Math.floor(J/7); var L = I - J; var M = 3 + Math.floor((L + 40)/44); var D = L + 28 - 31*Math.floor(M/4); // D = D-2; // subtract 2 days for Good Friday if (D <= 0){ D = D + 31; // correct day if we went back to March M = 3; // correct month } return parseInt(M, 10) + '/' + parseInt(D, 10); // return without any leading zeros }

If you find this code of value, donate a little to the cause. Think of the time you just saved!

USE AT YOUR OWN RISK!

Questions / Comments? Email me.