Asp.net mvc 如何将EF列表对象转换为dateTime类型的arrayList

我正在处理请假申请。我需要获取排除的日期并将其转换为dateTime数组

我使用以下方法部分实现了这一点。我创建了一个Helper文件夹，然后将以下类添加到该文件夹中：

namespace eLeave.Helpers
{
    public class BusinessDaysCalculator
    {
        public int Calculate(DateTime startDate, DateTime endDate, DateTime[] holidays)
        {
            startDate = FixStartDate(startDate);
            endDate = FixEndDate(endDate.Date);

            if (startDate > endDate)
                return 0;
            else
                return CalculateDifference(startDate, endDate, holidays);
        }



        private int CalculateDifference(DateTime startDate, DateTime endDate, DateTime[] holidays)
        {
            int difference = (int)(endDate - startDate).TotalDays;
            int weeks = difference / 7;
            if (endDate.DayOfWeek < startDate.DayOfWeek) weeks++;
            difference -= weeks * 2;
            difference -= HolidayCount(startDate, endDate, holidays);
            return difference + 1;
        }



        private int HolidayCount(DateTime startDate, DateTime endDate, DateTime[] holidays)
        {
            int holidayCount = 0;
            foreach (DateTime holiday in holidays)
            {
                if (HolidayInRange(startDate, endDate, holiday))
                    holidayCount++;
            }
            return holidayCount;
        }



        private DateTime FixStartDate(DateTime date)
        {
            if (date.DayOfWeek == DayOfWeek.Sunday)
                date = date.AddDays(1);
            else if (date.DayOfWeek == DayOfWeek.Saturday)
                date = date.AddDays(2);
            return date.Date;
        }



        private bool HolidayInRange(DateTime startDate, DateTime endDate, DateTime holiday)
        {
            return (holiday >= startDate
                && holiday <= endDate
                && holiday.DayOfWeek != DayOfWeek.Saturday
                && holiday.DayOfWeek != DayOfWeek.Sunday);
        }



        private DateTime FixEndDate(DateTime date)
        {
            if (date.DayOfWeek == DayOfWeek.Sunday)
                date = date.AddDays(-2);
            else if (date.DayOfWeek == DayOfWeek.Saturday)
                date = date.AddDays(-1);
            return date.Date;
        }
    }
}

该实现本来是要工作的，但在尝试使用下面的

holidays

DateTime Arrray时出现了错误

   DateTime[] holidays = new DateTime[3];
   holidays[0] = new DateTime(2017, 08, 15);
   holidays[1] = new DateTime(2017, 09, 1);    

我在上面的

holiday

数组中获得了包含排除日期的休假天数

我需要获取excludedates的值，并将其与我的类一起使用以使其正常工作

我在这里得到的错误如下：

Error   1   The best overloaded method match for 'eLeave.Helpers.BusinessDaysCalculator.Calculate(System.DateTime, System.DateTime, System.DateTime[])' has some invalid arguments  C:\Apps\WebApplications\eLeave\eLeave\eLeave\Controllers\RequestController.cs   100 32  eLeave


Error   2   Argument 3: cannot convert from 'eLeave.Models.ExcludedDate[]' to 'System.DateTime[]'   C:\Apps\WebApplications\eLeave\eLeave\eLeave\Controllers\RequestController.cs   100 67  eLeave

排除日期的模型如下所示：

public class ExcludedDate
{
    public byte Id { get; set; }
    public DateTime? ExcludedDates { get; set; }
}

---

您的查询返回的

ExcludedDate

类的数组不是类型

DateTime

-您需要一个

.Select（）

子句来仅选择对象的

ExcludedDate

属性

将查询更改为

DateTime[] excludedDates = _context.ExcludedDate
    .Where(d=>d.ExcludedDates >= StartDate && d.ExcludedDates <= EndDate)
    .Select(x => x.ExcludedDates)
    .ToArray();

DateTime[]excludedDates=\u context.ExcludedDate
其中（d=>d.ExcludedDates>=StartDate&&d.ExcludedDates x.ExcludedDates）
.ToArray（）；

---

请注意，不清楚为什么属性可以为null（该属性没有

null

值，而且名称与表名的关系有点混乱。我建议您将其更改为

public DateTime Date{get；set；}

不清楚您的要求。使用

.ToArray（）

是否将其转换为array@StephenMuecke：我已将问题编辑得更具体一些。但它已经是

DateTime[]

-这就是

.ToArray（）

does@StephenMuecke我将这些值传递到下面函数BusinessDaysCalculator calc=new BusinessDaysCalculator（）中的一个参数中；int days=calc.Calculate（StartDate、EndDate、excludedDates）；我有错误…我必须更新我的问题以包含我的帮助程序类，这样您才能更好地理解。@StephenMuecke我已编辑了问题以包含我的类used@StephenMueke：我会做必要的调整。非常感谢！

DateTime[] excludedDates = _context.ExcludedDate
    .Where(d=>d.ExcludedDates >= StartDate && d.ExcludedDates <= EndDate)
    .Select(x => x.ExcludedDates)
    .ToArray();