c# - 如何手动将带有列表的 View 模型映射到 dto

Question

我是后端开发的新手，在将 View 模型映射到具有列表的 dto 时遇到了一些问题。

你能帮我弄清楚映射器有什么问题吗？结果来自 dto 是正确的。我有一个包含 7 个项目的列表。当它映射到 View 时，它们就消失了。

这是 View 模型

public class StatisticsViewModel : BaseViewModel
{
    public string StartDate { get; set; }
    public string EndDate { get; set; }
    public string ProviderId { get; set; }
    public List<StatisticsTotalsViewModel> Totals { get; set; } = new List<StatisticsTotalsViewModel>();
    public List<StatisticsProvidersViewModel> Providers { get; set; } = new List<StatisticsProvidersViewModel>();
}

public class StatisticsTotalsViewModel
{
    public string PayerName { get; set; }
    public string PayerType { get; set; }
    public short Status { get; set; }
    public int TotalCount { get; set; }
    public decimal TotalBalance { get; set; }
}

这是dto

public class StatisticsDto
{
    public string StartDate { get; set; }
    public string EndDate { get; set; }
    public string ProviderId { get; set; }
    public List<StatisticsTotalsDto> Totals { get; set; } = new List<StatisticsTotalsDto>();
    public List<StatisticsProvidersDto> Providers { get; set; } = new List<StatisticsProvidersDto>();
}

public class StatisticsTotalsDto
{
    public string PayerName { get; set; }
    public string PayerType { get; set; }
    public short Status { get; set; }
    public int TotalCount { get; set; }
    public decimal TotalBalance { get; set; }
}

这是映射器

    public static StatisticsViewModel MapToView(StatisticsDto dto)
    {
        var viewmodel = new StatisticsViewModel();

        viewmodel.StartDate = dto.StartDate;
        viewmodel.EndDate = dto.EndDate;
        viewmodel.ProviderId = dto.ProviderId;

        var dtoTotals = new List<StatisticsTotalsDto>();
        var totals = new List<StatisticsTotalsViewModel>();

        foreach (var item in dtoTotals)
        {
            var totalsModel = new StatisticsTotalsViewModel();
            item.PayerName = totalsModel.PayerName;
            item.PayerType = totalsModel.PayerType;
            item.Status = totalsModel.Status;
            item.TotalBalance = totalsModel.TotalBalance;
            item.TotalCount = totalsModel.TotalCount;
            totals.Add(totalsModel);
        }

        viewmodel.Totals = totals;

       return viewmodel;

    }

Answer 1

这一行有问题。相反

var dtoTotals = new List<StatisticsTotalsDto>();

您需要接收 StatisticsTotalsDto 列表，而不是创建新的空列表

var dtoTotals = dto.Totals;