'IEnumerable<<anonymous type: DateTime DateTime, int NewCustomerCount, int NewBookingCount>>

Question

public async Task<IActionResult> GetMemberAndBookingLineChartData()
{
    var bookingData = _unitOfWork.Booking.GetAll(u => u.BookingDate >= DateTime.Now.AddDays(-30) && u.BookingDate.Date <= DateTime.Now).GroupBy(b => b.BookingDate.Date).Select(u => new
    {
        DateTime = u.Key,
        NewBookingCount = u.Count(),
    });
    var customerData = _unitOfWork.User.GetAll(u => u.CreatedDAt >= DateTime.Now.AddDays(-30) && u.CreatedDAt.Date <= DateTime.Now).GroupBy(b => b.CreatedDAt.Date).Select(u => new
    {
        DateTime = u.Key,
        NewCustomerCount = u.Count(),
    });

    var leftJoin = bookingData.GroupJoin(customerData, booking => booking.DateTime, customer => customer.DateTime, (booking, customer) => new
    {
        booking.DateTime,
        booking.NewBookingCount,
        NewCustomerCount = customer.Select(x => x.NewCustomerCount).FirstOrDefault()
    });
    var rightJoin = customerData.GroupJoin(bookingData, customer => customer.DateTime, booking => booking.DateTime, (customer, booking) => new
    {
        customer.DateTime,
        customer.NewCustomerCount,
        NewBookingCount = booking.Select(x => x.NewBookingCount).FirstOrDefault(),
    });

    //var mergedData = leftJoin.Union((rightJoin).OrderBy(x => x.DataTime).ToList());
    var mergedData = rightJoin.Union(leftJoin.OrderBy(x => x.DateTime)).ToList();

    var newBookingData = mergedData.Select(x => x.NewBookingCount).ToArray();
    var newCustomerData = mergedData.Select(x => x.NewCustomerCount).ToArray();
    var categories = mergedData.Select(x => x.DataTime.ToString("MM/dd/yyyy")).ToArray();
    List<CharData> charDataList = new()
    {
        new CharData
        {
            Name="New Bookings",
            Data=newBookingData
        },
        new CharData
        {
            Name="New Members",
            Data=newCustomerData
        }

    };
    LineChartVM lineChartVM = new()
    {
        Categories = categories,
        Series = charDataList
    };

    return Json(lineChartVM);
}

错误是

var mergedData = rightJoin.Union(leftJoin.OrderBy(x => x.DateTime)).ToList(); 

不起作用。

请给我一个解决方案

Answer 1

LINQ Union() 方法组合两个序列并删除重复项，但您似乎想保留所有元素然后对它们进行排序。

// Merge data using Concat instead of Union to retain all elements

var mergedData = rightJoin.Concat(leftJoin).OrderBy(x => x.DateTime).ToList();

通过使用 Concat 而不是 Union，您可以保留两个序列中的所有元素，然后您可以根据需要使用 OrderBy 对它们进行排序