I want to write a script in Js which tells number of days in a month and the test case must satisfy the below:
Enter a month: January. output-> January has 31 days.
Enter a month: JANUARY output-> January has 31 day
Enter a month: February output-> February has 28 days.
Enter a month: FEbruary output-> February has 28 days.
and my code is:
let a = prompt('Enter the month:');
let b = a.charAt(0).toUpperCase();
let c = a.slice(1, a.length).toLowerCase();
let Month = (b + c);
if ('January' === Month || 'March' === Month || 'May' === Month || 'July' === Month || 'Agust' === Month || 'October' === Month || 'December' === Month) {
console.log(`${Month} has 31 days`)
}
else if ('February' === Month) {
console.log(`${Month} has 28 days`);
}
else if ('April' === Month || 'June' === Month || 'September' === Month || 'November' === Month) {
console.log(`${Month} has 30 days`)
}
else{
console.log('Re-Enter');
}
It satisfies only first test case anybody help me out with the correct logic which satisfies all the test cases.
You can calculate retrieve the number of days for a month in any year by retrieving the date value of a Date for the next month with a date value of 0. Here's a small factory to determine the numbers of day per month (numeric or using a month name):
const getNDaysForMonthFactory = _ => {
const months = (`january,february,march,april,may,june,`+
`july,august,september,october,november,december`).split(',');
const byNr = (year, month) => new Date(year, month, 0).getDate();
return {
byNr,
byName: (year, month) => {
const m = months.findIndex( m => m === month.toLowerCase());
return m > -1
? byNr(year, m + 1)
: `[${month}] is not a valid month`;
},
};
}
const {byNr, byName} = getNDaysForMonthFactory();
console.log(`(byNr) 6 2022: ${byNr(2022, 6)} days`);
console.log(`(byNr) 2 2022: ${byNr(2022, 2)} days`);
console.log(`(byNr) 2 2000: ${byNr(2000, 2)} days`);
console.log(`(byName) february 2000: ${byName(2000, `FEBRuary`)} days`);
console.log(`(byName) nothing 2022: ${byName(2022, `nothing`)}`);
// so
showDays();
document.addEventListener(`change`, handle);
document.addEventListener(`keyup`, handle);
function showDays() {
const [month, year] = [
+document.querySelector(`#month`).value,
+document.querySelector(`#year`).value ];
document.querySelector(`#nDays`).textContent =
`${byNr(year, month)} days`;
}
function handle(evt) {
if (evt.target.id === `year` || evt.target.id === `month`) {
return showDays();
}
}<select id="month">
<option value="1" selected>January</option>
<option value="2">February</option>
<option value="3">March</option>
<option value="4">April</option>
<option value="5">May</option>
<option value="6">June</option>
<option value="7">July</option>
<option value="8">August</option>
<option value="9">September</option>
<option value="10">October</option>
<option value="11">November</option>
<option value="12">December</option>
</select>
<input id="year" type="number" value="2022"> <span id="nDays"></span>This is a modified version of @KooiInc response without the while loop
const getNDays = (year, month) => {
let daysOfMonth = 0;
let date = new Date(Date.UTC(year, month, 1, 0, 0, 0));
date.setDate(date.getDate() - 1);
return date.getDate();
}
console.log(`june 2022: ${getNDays(2022, 6)} days`);
console.log(`february 2022: ${getNDays(2022, 2)} days`);
console.log(`february 2000: ${getNDays(2000, 2)} days`);
console.log(`february 1900: ${getNDays(1900, 2)} days`);
// so
showDays();
document.addEventListener(`change`, handle);
function showDays() {
const [month, year] = [
+document.querySelector(`#month`).value,
+document.querySelector(`#year`).value ];
document.querySelector(`#nDays`).textContent =
`${getNDays(year, month)} days`;
}
function handle(evt) {
if (evt.target.id === `year` || evt.target.id === `month`) {
return showDays();
}
}<select id="month">
<option value="1" selected>January</option>
<option value="2">February</option>
<option value="3">March</option>
<option value="4">April</option>
<option value="5">May</option>
<option value="6">June</option>
<option value="7">July</option>
<option value="8">August</option>
<option value="9">September</option>
<option value="10">October</option>
<option value="11">November</option>
<option value="12">December</option>
</select>
<input id="year" type="number" value="2022"> <span id="nDays"></span>We can create a formatDaysInMonth() function that will take a monthName such as January, FEBRUARY, etc and a year and return the formatted month and days, like "February 2020 has 29 days":
function monthNameToMonth(monthName) {
const months = { january: 1, february: 2, march: 3, april: 4, may: 5, june: 6, july: 7, august: 8, september: 9, october: 10, november: 11, december: 12 };
return months[monthName.toLowerCase()]
}
function getDaysInMonth(year, month) {
return new Date(year, month, 0).getDate();
}
function formatDaysInMonth(year, monthName) {
let month = monthNameToMonth(monthName);
let days = getDaysInMonth(year, month);
monthName = monthName.toUpperCase().slice(0,1) + monthName.toLowerCase().slice(1);
return `${monthName} ${year} has ${days} days`;
}
let monthName = prompt('Enter the month name:');
let year = prompt('Enter the year:');
console.log(formatDaysInMonth(year, monthName)).as-console-wrapper { max-height: 100% !important; }