如何确定ASP.NET日历显示的整个日期范围?

查看ASP.NET Calendar控件公开的公共成员,我不相信这些信息可以从Calendar控件中获得。

你有一些选择作为“变通办法”,虽然不是很好…但它们会起作用。

1. 您可以手动计算第一周的值
2. 您可以处理“day render”事件来处理各个日期的绑定,并记录最小/最大值。

虽然两者都不优雅,但这是唯一的现实选择

编辑

这里重要的是定义结构良好的页面级属性,以便在绑定事件期间保存项目,但要确保如果某个月发生了变化等,不会错误地加载项目等。

我写了几个方法来帮助解决这个问题。只需传入Calendar.VisibleDate:

public static DateTime GetFirstDateOfMonth(DateTime date)
{
    return new DateTime(date.Year, date.Month, 1);
}

public static DateTime GetFirstDisplayedDate(DateTime date)
{
    date = GetFirstDateOfMonth(date);
    return date.DayOfWeek == DayOfWeek.Sunday ? date.AddDays(-7) : date.AddDays((int)date.DayOfWeek * -1);
}

public static List<DateTime> GetDisplayedDates(DateTime date)
{
    date = GetFirstDisplayedDate(date);

    List<DateTime> dates = new List<DateTime>();
    for (int i = 0; i < 42; i++)
    {
        dates.Add(date.AddDays(i));
    }

    return dates;
}

我自己也在调查这件事,直接到这里来了。我个人倾向于选择第二种,因为另一种选择很混乱。罗尼的版本很好,但不幸的是,它没有考虑到不同文化的第一天。

使用Reflector,我们可以看到它是如何在内部完成的:

    ...
    DateTime visibleDate = this.EffectiveVisibleDate();
    DateTime firstDay = this.FirstCalendarDay(visibleDate);
    ...

private System.Globalization.Calendar threadCalendar = 
    DateTimeFormatInfo.CurrentInfo.Calendar;

private DateTime EffectiveVisibleDate()
{
    DateTime visibleDate = this.VisibleDate;
    if (visibleDate.Equals(DateTime.MinValue))
    {
        visibleDate = this.TodaysDate;
    }
    if (this.IsMinSupportedYearMonth(visibleDate))
    {
        return this.minSupportedDate;
    }
    return this.threadCalendar.AddDays(visibleDate, 
        -(this.threadCalendar.GetDayOfMonth(visibleDate) - 1));
}


private DateTime FirstCalendarDay(DateTime visibleDate)
{
    DateTime date = visibleDate;
    if (this.IsMinSupportedYearMonth(date))
    {
        return date;
    }
    int num = ((int) 
       this.threadCalendar.GetDayOfWeek(date)) - this.NumericFirstDayOfWeek();
    if (num <= 0)
    {
        num += 7;
    }
    return this.threadCalendar.AddDays(date, -num);
}

private int NumericFirstDayOfWeek()
{
    if (this.FirstDayOfWeek != FirstDayOfWeek.Default)
    {
        return (int) this.FirstDayOfWeek;
    }
    return (int) DateTimeFormatInfo.CurrentInfo.FirstDayOfWeek;
}

private bool IsMinSupportedYearMonth(DateTime date)
{
    return this.IsTheSameYearMonth(this.minSupportedDate, date);
}

private bool IsTheSameYearMonth(DateTime date1, DateTime date2)
{
    return (((this.threadCalendar.GetEra(date1) == 
                   this.threadCalendar.GetEra(date2)) &&
          (this.threadCalendar.GetYear(date1) == 
                   this.threadCalendar.GetYear(date2))) &&
          (this.threadCalendar.GetMonth(date1) ==
                   this.threadCalendar.GetMonth(date2)));
}

米切尔, bool m_FirstDay=false

在day_渲染函数中

if(m_FirstDay == false)
{
    DateTime firstDate;
    DateTime lastDate;

    firstDate = e.Day.Date;
    lastDate = firstDate.AddDays(41);

    m_FirstDay = true;
}

How to Remove the Last Week Of a Calendar