无效日期在IE中不返回为无效[重复]

function isValidDateString(s) {
    "use strict";

    if (typeof s !== "string") {
        return false; // not a string, exit.
    }

    var parts = s.split("/");

    if (parts.length !== 3) {
        return false; // unexpected number of slashes. exit.
    }

    var d31 = [1, 3, 5, 7, 8, 10, 12];
    var d30 = [4, 6, 9, 11];

    var mm = parseInt(parts[0]);
    var dd = parseInt(parts[1]);
    var yyyy = parseInt(parts[2]);

    // empirical testing in Chrome & IE11 to get this value. YMMV.
    var maxYear = 275760;

    var isValidYear = !isNaN(yyyy) && yyyy <= maxYear;

    var isDivisbleBy4 = (yyyy % 4 === 0);
    var isDivisbleBy100 = (yyyy % 100 === 0);
    var isDivisbleBy400 = (yyyy % 400 === 0);
    var isLeapYear = (isDivisbleBy4 && !isDivisbleBy100) || isDivisbleBy400;

    var isValidMonth = !isNaN(mm) && (mm >= 1 && mm <= 12);
    if (!isValidMonth) {
        return false;
    }

    var maxDaysInMonth = 28;

    if (d31.indexOf(mm) > -1) {
        maxDaysInMonth = 31;
    } else if (d30.indexOf(mm) > -1) {
        maxDaysInMonth = 30;
    } else if (isLeapYear) {
        maxDaysInMonth = 29;
    }

    var isValidDay = !isNaN(dd) && (dd > 0 && dd <= maxDaysInMonth);
    if (!isValidDay) {
        return false;
    }

    return isValidMonth && isValidDay && isValidYear;
}

var testsThatShouldFail = [
    '13/77/7777', // lousy Smarch weather!
    '2/29/2018',
    '9/12/275761',
    '4/31/2016',
    '6/35/2019',
];

var testsThatShouldPass = [
    '1/1/1900',
    '2/29/2000',
    '2/29/2016',
    '9/12/275760',
    '8/16/2018',
];

console.log('should fail', testsThatShouldFail.map(isValidDateString));
console.log('should pass', testsThatShouldPass.map(isValidDateString));