如何根据月份向 ObservableCollection 添加项目？

Question

我有一个 ObservableCollection 用于存储月份事件。我正在添加如下月份的事件：其中 AllItems 是我的 ObservableCollection.

AllItems = new ObservableCollection<EventsHB>();

        EventsHB januvaryGroup = new EventsHB() { month = "January" };
        EventsHB februvaryGroup = new EventsHB() { month = "February" };
        EventsHB marchGroup = new EventsHB() { month = "March" };
        EventsHB aprilGroup = new EventsHB() { month = "April" };
        EventsHB mayGroup = new EventsHB() { month = "May" };
        EventsHB juneGroup = new EventsHB() { month = "June" };
        EventsHB julyGroup = new EventsHB() { month = "July" };
        EventsHB augustGroup = new EventsHB() { month = "August" };
        EventsHB septemberGroup = new EventsHB() { month = "September" };
        EventsHB octoberGroup = new EventsHB() { month = "October" };
        EventsHB novemberGroup = new EventsHB() { month = "November" };
        EventsHB decemberGroup = new EventsHB() { month = "December" };

        foreach (var item in allItem)
        {
            EventsHBTwo hb = item;
            if (hb.month == "January")
            {
                januvaryGroup.Add(hb.eventTO);
            }
            else if (hb.month == "February")
            {
                februvaryGroup.Add(hb.eventTO);
            }
            else if (hb.month == "March")
            {
                marchGroup.Add(hb.eventTO);
            }
            else if (hb.month == "April")
            {
                aprilGroup.Add(hb.eventTO);
            }
            else if (hb.month == "May")
            {
                mayGroup.Add(hb.eventTO);
            }
            else if (hb.month == "June")
            {
                juneGroup.Add(hb.eventTO);
            }
            else if (hb.month == "July")
            {
                julyGroup.Add(hb.eventTO);
            }
            else if (hb.month == "June")
            {
                juneGroup.Add(hb.eventTO);
            }
            else if (hb.month == "July")
            {
                julyGroup.Add(hb.eventTO);
            }
            else if (hb.month == "August")
            {
                augustGroup.Add(hb.eventTO);
            }
            else if (hb.month == "September")
            {
                septemberGroup.Add(hb.eventTO);
            }
            else if (hb.month == "October")
            {
                octoberGroup.Add(hb.eventTO);
            }
            else if (hb.month == "November")
            {
                novemberGroup.Add(hb.eventTO);
            }
            else if (hb.month == "December")
            {
                decemberGroup.Add(hb.eventTO);
            }
        }
 try
        {
            List<EventsHB> MonthsData = new List<EventsHB>() { null, januvaryGroup, februvaryGroup, marchGroup, aprilGroup, marchGroup, juneGroup, julyGroup, augustGroup, septemberGroup, octoberGroup, novemberGroup, decemberGroup };
            int currentMonth = 12;
            while (AllItems.Count < 12)
            {
                AllItems.Add(MonthsData[currentMonth]);
                currentMonth++;
                if (currentMonth == 13)
                    currentMonth = 1;
            }
        }
        catch(Exception e)
        {
            Debug.WriteLine("Event Exception:>>"+e);
        }

是否可以根据月份添加事件？如果当前月份是 August，我需要先将 august 事件添加到集合中。然后 September 到 July。不使用 12 if 条件可以吗？

Answer 1

您可以使用此逻辑 :- 我已经使用您需要使用模型修改的字符串构建了逻辑 class。 MonthsData 将是您的数据：- januvaryGroup、februvaryGroup 等。您需要在此之前添加一个空组。

List<string> MonthsData = new List<string>() { "", "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" };
int currentMonth = DateTime.Now.Month;
ObservableCollection<string> list = new ObservableCollection<string>(new List<string>());
while(list.Count < 12)
{
     list.Add(MonthsData[currentMonth]);
     currentMonth++;
     if (currentMonth == 13)
          currentMonth = 1;
}

如果您有任何疑问，请告诉我。

如何根据月份向 ObservableCollection 添加项目？

How to add items to an ObservableCollection based on the month?

observablecollection

xamarin.forms