JS判断是否为“YYYYMMDD”式的日期

?

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29

function isDate8(sDate) {           if (!/^[0-9]{8}$/.test(sDate)) {               return false;           }           var year, month, day;           year = sDate.substring(0, 4);           month = sDate.substring(4, 6);           day = sDate.substring(6, 8);           var iaMonthDays = [31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]           if (year < 1700 || year > 2500) return false           if (((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0)) iaMonthDays[1] = 29;           if (month < 1 || month > 12) return false           if (day < 1 || day > iaMonthDays[month - 1]) return false           return true       }