如何使用 DateTime.DaysInMonth 将一个月中的天数填充到组合框

Question

我正在尝试用这个

用所选月份的天数填充组合框

    private void cboSelectMonth_SelectedIndexChanged(object sender, EventArgs e)
    {
       if (cboSelectMonth.SelectedIndex >= 0)
       {
            int year = Convert.ToInt32(cboSelectYear.SelectedValue);
            int month = Convert.ToInt32(cboSelectMonth.SelectedValue);

            this.cboSelectDay.DisplayMember = "Text";
            this.cboSelectDay.ValueMember = "Value";

            int dayCount = DateTime.DaysInMonth(year, month);
            var days = new[ dayCount+1 ] { };

            for (int i = 1; i < dayCount +1; i++)
            {
                days[i] = new { Text = Convert.ToString(i), Value = i };
                //cboSelectDay.Items.Add(i);
                //   days[]  { new { Text = Convert.ToString(i), Value = i } };
            }

            this.cboSelectDay.DataSource = days;

            DateTime now = DateTime.Now;
            int dayValue = now.Day;

            cboSelectDay.SelectedIndex = dayValue - 1; 
       }
    }

因此，我试图以一个列出当月所有日期的 ComboBox 结束。例如，选择 9 月将使 ComboBox 增加 30 天，而选择 10 月将为您增加 31 天，依此类推。我收到两个错误。第一个在 var days = new[ dayCount+1 ] { }; 行上，表示 ']' 是预期的。第二个错误出现在 days[i] = new { Text = Convert.ToString(i), Value = i }; 行上，上面写着 Cannot implicitly convert type 'AnonymousType#1' to 'int'

我正在尝试做一些类似于我在月中所做的事情，它确实有效（下面的代码块）。我做错了什么？

    private void FillMonthCombobox()
    {
        this.cboSelectMonth.DisplayMember = "Text";
        this.cboSelectMonth.ValueMember = "Value";

        var months = new[] 
        { 
            new { Text = "January", Value = 1 }, 
            new { Text = "February", Value = 2 }, 
            new { Text = "March", Value = 3 }, 
            new { Text = "April", Value = 4 }, 
            new { Text = "May", Value = 5 }, 
            new { Text = "June", Value = 6 }, 
            new { Text = "July", Value = 7 }, 
            new { Text = "Aughust", Value = 8 }, 
            new { Text = "September", Value = 9 }, 
            new { Text = "October", Value = 10 }, 
            new { Text = "November", Value = 11 }, 
            new { Text = "December", Value = 12 } 
        };
        this.cboSelectMonth.DataSource = months;

        DateTime now = DateTime.Now;
        int monthValue = now.Month;
        cboSelectMonth.SelectedIndex = monthValue - 1;
    }

编辑： 我现在可以填充 ComboBox，但如何将 Text = day 和 Value = day 添加到循环中以便稍后引用该值？在这个循环的情况下，它们将是相同的，但在我正在使用的其他一些循环的情况下，它们将是不同的。本质上，我想在第二个代码块中做同样的事情，但有一个循环。

Answer 1

很简单，但你也必须指定年份。注意二月和闰年！

int year = 2015;
int month = 5;
int[] days = Enumerable.Range(1, DateTime.DaysInMonth(year, month)).ToArray();

之后可以指定为DataSource:

cboSelectDay.DataSource = days;
cboSelectDay.DataBind();

Answer 2

使用您的一般方法，这确实有效：

int thisMonthsDays = DateTime.DaysInMonth(DateTime.Now.Year, DateTime.Now.Month);

for (int i = 1; i <= thisMonthsDays; i++) { comboBox1.Items.Add(i);  }

它用预期的 31 天（5 月）填充 comboBox1。

努力完成并更好地掌握它，我认为这次更新会有所帮助：

先来个小的class:

public class YearClass
    {
        public int IndexOfMonth { get; set; }
        public string DayName { get; set; }
    }

现在添加将月份的日期绑定到组合框的代码：

 List<YearClass> months = new List<YearClass>();
            int thisMonthsDays = DateTime.DaysInMonth(DateTime.Now.Year, DateTime.Now.Month);

            for (int i = 1; i <= thisMonthsDays; i++)
            {
                YearClass currentDay = new YearClass();
                    currentDay.IndexOfMonth = i;
                    DateTime dt = new DateTime(DateTime.Now.Year, DateTime.Now.Month, i);
                    currentDay.DayName = dt.DayOfWeek.ToString();
                    months.Add(currentDay);
            }

            comboBox1.DataSource = months;
            comboBox1.DisplayMember = "DayName";

输出结果如下：

Answer 3

你可以这样做 - 我正在传递年月的硬编码值

for (int i = 0; i < DateTime.DaysInMonth(2015, 05); i++)
{ 
cmbMonth.Items.Add(i.ToString());
}

如果您有任何其他要求，请告诉我

如何使用 DateTime.DaysInMonth 将一个月中的天数填充到组合框

How do I fill a Combobox with days in month using an DateTime.DaysInMonth

c#

combobox

winforms