How to check current date is available or not in the date array in typescript-CodePudding

How to check current date is available or not in the date array in typescript. Tried to check with below code, If current is available in between the array dates, still its giving result as false. Kindly suggest me the solution.

let time1= ['5:00:00 PM','5:59:59 PM'];
const dateCheck = new Date().toLocaleTimeString('en-US');
const status = time1.includes(dateCheck) ?true:false;
console.log(status);

CodePudding user response：

include only checks for an exact match on the array, between is not included

to use include you would have to populate the array with every possible time between the 2,

however you can use > >= and < <= to check for between

const dateCheck:date = new Date().toLocaleTimeString('en-US');
const time1:string[] = ['12:00:00 PM','12:59:59 PM'];

const status: boolean = (time1[0]<=dateCheck && time1[1]>=dateCheck)
console.log(dateCheck,status);

//output "12:56:13 PM", true

this is using an alphabetic compare not a date compare so will yield odd results, your should really convert to timestamps or compare the date components, to compare properly eg

const dateCheck:date = new Date()
const time1 = [{
    hour:12,
  minute:0
},{
    hour:17,
  minute:59
}]

//convert to number of minutes since midnight so you can use a numeric compare
const dayMins = dateCheck.getHours()*60  dateCheck.getMinutes()
const start = time1[0].hour*60  time1[0].minute
const end = time1[1].hour*60  time1[1].minute

const status = (
    dayMins>=start &&  dayMins<=end
)
console.log(dateCheck.toLocaleTimeString(),status)

CodePudding user response：

A lot of the other answers here use string-based comparisons. To ensure the correct results, you should instead use numeric comparisons. Especially when checking between different days such as between 10PM and 2AM.

function checkTime(timeCheck, timeRange) {
    const datePart = '2000-01-01 ', // used to anchor times to the same date
        d0 = new Date(datePart   timeRange[0]).getTime(),
        d1 = new Date(datePart   timeRange[1]).getTime(),
        dToCheck = new Date(datePart   (typeof timeCheck === 'string' ? timeCheck : timeCheck.toLocaleTimeString('en-US'))).getTime();

    if (isNaN(d0) || isNaN(d1) || isNaN(dToCheck)) throw new TypeError('invalid time format');

    return d0 < d1
        ? d0 <= dToCheck && dToCheck <= d1  // handle times on the same day
        : d1 <= dToCheck || dToCheck <= d0; // handle times on different days
}

const timeRange = ['5:00:00 PM','5:59:59 PM'];

checkTime('5:15:00 PM', timeRange); // true
checkTime('5:15 PM', timeRange); // true
checkTime('5:15:00 AM', timeRange); // false
checkTime('5:15 AM', timeRange); // false
checkTime(new Date().toLocaleTimeString('en-US'), timeRange); // depends
checkTime(new Date(), timeRange); // depends
checkTime(new Date('2021-01-01T12:00:00Z'), timeRange); // depends on timezone

If you want to perform this check against many items, you should instead use currying to squeeze out some extra performance by pre-calculating the range to compare against.

function buildCheckTime(startTime, endTime) {
    const datePart = '2000-01-01 ', // used to anchor times to the same date
        d0 = new Date(datePart   timeRange[0]).getTime(),
        d1 = new Date(datePart   timeRange[1]).getTime();

    if (isNaN(d0) || isNaN(d1)) throw new TypeError('invalid time format');

    return d0 < d1
        ? function(timeCheck) { // handle times on the same day
            const dToCheck = new Date(datePart   (typeof timeCheck === 'string' ? timeCheck : timeCheck.toLocaleTimeString('en-US'))).getTime();

            if (isNaN(dToCheck)) throw new TypeError('invalid time format');

            return d0 <= dToCheck && dToCheck <= d1;
        }
        : function (timeCheck) { // handle times on different days
            const dToCheck = new Date(datePart   (typeof timeCheck === 'string' ? timeCheck : timeCheck.toLocaleTimeString('en-US'))).getTime();

            if (isNaN(dToCheck)) throw new TypeError('invalid time format');

            return d1 <= dToCheck || dToCheck <= d0;
        }
}

const checkTime = buildCheckTime('5:00:00 PM','5:59:59 PM');

checkTime('5:15:00 PM'); // true
checkTime('5:15 PM'); // true
checkTime('5:15:00 AM'); // false
checkTime('5:15 AM'); // false
checkTime(new Date().toLocaleTimeString('en-US')); // depends
checkTime(new Date()); // depends
checkTime(new Date('2021-01-01T12:00:00Z')); // depends on timezone

CodePudding user response：

let time1= ['5:00:00 PM','5:59:59 PM'];
const dateCheck = new Date().toLocaleTimeString('en-US');
const status = time1[0] < dateCheck && time1[1] > dateCheck ?true:false;
console.log(status);

try in this way as includes is like indexOf function of array it does not checks within it checks for same match for that value for the array being used

CodePudding user response：

let times = ['5:00:00 PM', '5:59:59 PM'];

startTime = new Date('2022-01-01 '   times[0]).getTime()
endTime = new Date('2022-01-01 '   times[1]).getTime()


testTime = new Date('2022-01-01 '   '5:30:00 PM').getTime()
const isBetween = testTime > startTime && testTime < endTime;