Question

我有一个HTML页面，包含3个月，日和年的下拉菜单，我想知道是否有办法根据月份和年份正确填充月份下拉列表。

我之前没有在客户端做过这个，但看起来像jQuery DatePicker这样的很多控件都是在幕后做的。

Answer 1

据我所知，没有（整洁的）内置功能。我曾写过一次：

// note that month is 0-based, like in the Date object. Adjust if necessary.
function getNumberOfDays(year, month) {
    var isLeap = ((year % 4) == 0 && ((year % 100) != 0 || (year % 400) == 0));
    return [31, (isLeap ? 29 : 28), 31, 30, 31, 30, 31, 31, 30, 31, 30, 31][month];
}

Answer 2

您可以使用日期对象：

var monthStart = new Date(year, month, 1);
var monthEnd = new Date(year, month + 1, 1);
var monthLength = (monthEnd - monthStart) / (1000 * 60 * 60 * 24)

使用Date个对象的算术给出了毫秒数。

这甚至适用于12月; Date构造函数通过环绕来处理超出范围的参数。

请注意，month从零开始（必须介于0和11之间）

Answer 3

从其他帖子复制：Get number days in a specified month using javascript?

//Month is 1 based
function daysInMonth(month,year) {
return new Date(year, month, 0).getDate();
}

//July
daysInMonth(7,2009); //31
//February
daysInMonth(2,2009); //28
daysInMonth(2,2008); //29

@c_harm的所有学分，真的很棒的解决方案

Answer 4

Date.prototype.daysinMonth: function(){
    var d= new Date(this.getFullYear(), this.getMonth()+1, 0);
    return d.getDate();
}

function daysinMonthfromInput(month,year){
    return (new Date(year,month-1,1)).daysinMonth();
}

alert(daysinMonthfromInput(2,2011));

Answer 5

这是一个班轮。假设您说的是1月= 1，2月= 2等...（正常）这是闰年的例子：

var y = 2012;
var m = 2;
var daysInMonth = new Date(y,m,1,-1).getDate();

Answer 6

我在我当前的项目中使用这种方法，发现我需要纠正舍入错误。因此，我不必在代码中使用monthLength，而是使用它：

monthLength.toFixed(0)

例如，如果我有一个存储文本日期字段的对象，它可能如下所示：

obj.month = theMonths[mm - 1] + " " + monthLength.toFixed(0) + ", " + obj.year;

Answer 7

你实际上可以使用它：

var curdate = new Date（）; DaysMonth = 32 - new Date（curdate.getYear（），curdate.getMonth（），32）。getDate（）;

）

Answer 8

class Request(_Request):
    """
    HTTP request class.
    This is a Pyramid Request object augmented with type hinting information for Websauna-specific functionality.
    To know more about request read also
    * py:class:`pyramid.request.Request` documentation
    * py:class:`webob.request.Request` documentation

    Counterintuitively, this request is also available in non-HTTP applications like command line applications and timed tasks. 
    These applications do not get request URL from a front end HTTP webserver, but a faux request is constructed pointing to the website URL taken from ``websauna.site_url`` setting. 
    This is to allow similar design patterns and methodology to be applied in HTTP and non-HTTP applications.

    By setting variables in ``__type_hinting__()`` based on arguments types allows IDEs to infer type information when you hint your views as::

         from websauna.system.http import Request

         def hello_world(request: Request):
             request.  # <-- When typing, here autocompletion kicks in.

    """

    def __type_hinting__(self, user: Optional[User], dbsession: Session, session: ISession, admin: Admin, registry: Registry):
        """
        A dummy helper function to tell IDEs about reify'ed variables.
        :param user: The logged in user. None if the visitor is anonymous.
        :param dbsession: Current active SQLAlchemy session
        :param session: Session data for anonymous and logged in users.
        :param admin: The default admin interface of the site. Note that the site can have several admin interfaces for different purposes.
        :param registry: Pyramid registry's. E.g. 
            :py:attr:`pyramid.registry.Registry.settings` for reading settings and :py:meth:`pyramid.registry.Registry.notify` for sending events.
        """
        self.user = user
        self.dbsession = dbsession
        self.session = session
        self.admin = admin
        self.registry = registry

Javascript：计算给定年份的月数

8 个答案: