Question

private void GenerateMonth(bool SetCurruntMonth)
{
   drpMonth.Items.Clear();
   int year = drpYear.SelectedIndex != 0 ? ((drpYear.SelectedValue != "") ? Convert.ToInt32(drpYear.SelectedValue) : DateTime.Now.Year)
                       : DateTime.Now.Year;

    int months = (DateTime.Now.Year == year) ? DateTime.Now.Month : 12;
    for (int i = 1; i <= months; i++)
    {
        drpMonth.Items.Add(new ListItem(CultureInfo.CurrentCulture.DateTimeFormat.GetMonthName(i), i.ToString()));
        }
        if (SetCurruntMonth == true && DateTime.Now.Year == year)
        {
            drpMonth.Items.FindByValue(DateTime.Now.AddMonths(-1).ToString()).Selected = true;
        }
        else
        {
            drpMonth.SelectedIndex = 0;
        }
    }

Answer 1

您的方法应如下所示：

  private void GenerateMonth(bool SetCurruntMonth, DateTime currentDate)
    {
        drpMonth.Items.Clear();
        int year = drpYear.SelectedIndex != 0 ? ((drpYear.SelectedValue != "") ? Convert.ToInt32(drpYear.SelectedValue) : currentDate.Year)
                            : currentDate.Year;

        //int months = (currentDate.Year == year) ? currentDate.Month : 12;
        int months = 12;

        for (int i = 1; i <= months; i++)
        {
            drpMonth.Items.Add(new ListItem(CultureInfo.CurrentCulture.DateTimeFormat.GetMonthName(i), i.ToString()));
        }
        if (SetCurruntMonth == true && currentDate.Year == year)
        {
            if (currentDate.Month > 1)
                drpMonth.Items.FindByValue(currentDate.AddMonths(-1).Month.ToString()).Selected = true;
            else
                drpMonth.Items.FindByValue("1").Selected = true;
        }
        else
        {
            drpMonth.SelectedIndex = 0;
        }
    }

问题是当您尝试在下拉列表中选择它时，您没有检查Month属性。而是检查完整的日期时间值。

修改：我已修复您的问题，但我还添加了一个额外的日期参数，以便于测试，如果您愿意，可以替换它。

编辑2 ：注释掉“月”逻辑，以便所有月份都显示在下拉列表中。

Answer 2

private void GenerateMonth(bool SetCurruntMonth, DateTime currentDate)
     {
        drpYear.ClearSelection();
        drpMonth.Items.Clear();
        int year = drpYear.SelectedIndex != 0 ? ((drpYear.SelectedValue != "") ? Convert.ToInt32(drpYear.SelectedValue) : currentDate.Year) : currentDate.Year;

        int months = (currentDate.Year == year) ? currentDate.Month : 12;
        int i;
        for ( i = 1; i <= 12; i++)
        {
            drpMonth.Items.Add(new ListItem(CultureInfo.CurrentCulture.DateTimeFormat.GetMonthName(i), i.ToString()));
        }
       //int month;
        if (SetCurruntMonth == true && currentDate.Year == year)
        {
            if (currentDate.Month >= 1)
            {
                drpMonth.Items.FindByValue(currentDate.AddMonths(-1).Month.ToString()).Selected = true;
               // month = Convert((currentDate.AddMonths(-1).Month.ToString()).Selected = true);
            }
            else
                drpMonth.Items.FindByValue("1").Selected = true;
             //drpYear.Items.FindByValue((DateTime.Now.Year-1).ToString()).Selected = true;
            if (currentDate.Month == 1)
            {
               DateTime year1 = (currentDate.AddYears(-1));
               int yy = Convert.ToInt16(year1.Year);
enter code here
                drpYear.Items.Add(new ListItem(Convert.ToString(year)));
                drpYear.SelectedValue= Convert.ToString(yy);
            }
        }
        else
        {
            drpMonth.SelectedIndex = 0;
        }
    }

如何使用c＃在下拉列表中加载上个月的名称

2 个答案: