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复制代码 代码如下:

/**

* jscript.datetime package

* This package contains utility functions for working with dates and times.

*/

/*命名空间*/

if (typeof jscript == 'undefined') {

jscript = function() { }

}

jscript.datetime = function() { }

/**

* This function will return the number of days in a given month and year,

* taking leap years into account.（这个函数返回所给某年、某月的天数，并且考虑了闰年的情况）

*

* @param inMonth The month, where January = 1 and December = 12.

* @param inYear The year to check the month in.

* @return The number of days in the specified month and year.

*/

jscript.datetime.getNumberDaysInMonth = function(inMonth, inYear) {

inMonth = inMonth - 1;

var leap_year = this.isLeapYear(inYear);

if (leap_year) {

leap_year = 1;

} else {

leap_year = 0;

}

/*4, 6, 9, 11 月为 30 天，注意上面的 inMonth = inMonth - 1*/

if (inMonth == 3 || inMonth == 5 || inMonth == 8 || inMonth == 10) {

return 30;

} else if (inMonth == 1) {/*2 月为 28 或者 29 天，视是否为闰年而定*/

return 28 + leap_year;

} else {/*其它月则为 31 天*/

return 31;

}

} // End getNumberDaysInMonth().

/**

* This function will determine if a given year is a leap year.

*（这个函数用来确定是否为闰年）

* @param inYear The year to check.

* @return True if inYear is a leap year, false if not.

*/

jscript.datetime.isLeapYear = function(inYear) {

if ((inYear % 4 == 0 && !(inYear % 100 == 0)) || inYear % 400 == 0) {

return true;

} else {

return false;

}

} // End isLeapYear().