2

我正在尝试将一系列对象列表添加到新列表中，但收到以下消息：

无法将类型“void”隐式转换为“System.Collections.Generic.List”

这是我正在尝试的：

Detalhes = new List<DetalhesExcel>() {
    new DetalhesExcel()
    {
        NumColunaInicial = 23,
        Coluna1 = "Representante",
        Coluna2 = "ValorRepasse",
        Coluna3 = "KmRepasse"
    }
}.AddRange(ocorrencias.Where(x => x.Conclusao != "PRÓPRIO")
    .GroupBy(x => x.Representante)
    .Select(x => new DetalhesExcel
    {
        NumColunaInicial = 23,
        Coluna1 = x.First().Representante,
        Coluna2 = x.Sum(y => y.ValorRepasse).ToString(),
        Coluna3 = x.Sum(y => y.KmRepasse).ToString()
    }).ToList())

我需要做什么？

DetalhesExcel 类：

public class DetalhesExcel
{
    public int NumColunaInicial { get; set; }
    public string Coluna1 { get; set; }
    public string Coluna2 { get; set; }
    public string Coluna3 { get; set; }
    public string Coluna4 { get; set; }
    public string Coluna5 { get; set; }
}
4

5 回答 5

2

我想你想要的是这样的

    class Program
{
    static void Main(string[] args)
    {
        List<Ocorrencia> ocorrencias = new List<Ocorrencia>() {
            new Ocorrencia() {
                Conclusao = "teste",
                KmRepasse = 1,
                Representante = "um",
                ValorRepasse = 2
            }
        };



        var Detalhes = new List<DetalhesExcel>() {
                new DetalhesExcel()
                {
                    NumColunaInicial = 23,
                    Coluna1 = "Representante",
                    Coluna2 = "ValorRepasse",
                    Coluna3 = "KmRepasse"
                }
            }.Concat(ocorrencias.Where(x => x.Conclusao != "PRÓPRIO")
                            .GroupBy(x => x.Representante)
                            .Select(x => new DetalhesExcel
                            {
                                NumColunaInicial = 23,
                                Coluna1 = x.First().Representante,
                                Coluna2 = x.Sum(y => y.ValorRepasse).ToString(),
                                Coluna3 = x.Sum(y => y.KmRepasse).ToString()
                            }).ToList());

    }
}

public class Ocorrencia
{
    public string Conclusao { get; set; }
    public string Representante { get; set; }
    public int KmRepasse { get; set; }
    public int ValorRepasse { get; set; }
}

public class DetalhesExcel
{
    public int NumColunaInicial { get; set; }
    public string Coluna1 { get; set; }
    public string Coluna2 { get; set; }
    public string Coluna3 { get; set; }
    public string Coluna4 { get; set; }
    public string Coluna5 { get; set; }
}
于 2019-02-21T17:23:48.233 回答
1

AddRange返回无效。因此将 List 初始化AddRange分为两部分。

Detalhes = new List<DetalhesExcel>() {
    new DetalhesExcel()
    {
        NumColunaInicial = 23,
        Coluna1 = "Representante",
        Coluna2 = "ValorRepasse",
        Coluna3 = "KmRepasse"
    }
};

Detalhes.AddRange(ocorrencias.Where(x => x.Conclusao != "PRÓPRIO")
    .GroupBy(x => x.Representante)
    .Select(x => new DetalhesExcel
    {
        NumColunaInicial = 23,
        Coluna1 = x.First().Representante,
        Coluna2 = x.Sum(y => y.ValorRepasse).ToString(),
        Coluna3 = x.Sum(y => y.KmRepasse).ToString()
    }).ToList())
于 2019-02-21T17:14:37.513 回答
1

由于AddRange修改了现有的序列并返回void，因此它不能在方法链中用作赋值的一部分。但是，您可以使用该Concat方法，该方法通过将第一个与第二个连接起来创建一个新序列，然后返回该新序列：

Detalhes = new List<DetalhesExcel>()
{
    new DetalhesExcel()
    {
        NumColunaInicial = 23,
        Coluna1 = "Representante",
        Coluna2 = "ValorRepasse",
        Coluna3 = "KmRepasse"
    }
}.Concat(ocorrencias.Where(x => x.Conclusao != "PRÓPRIO")
    .GroupBy(x => x.Representante)
    .Select(x => new DetalhesExcel
    {
        NumColunaInicial = 23,
        Coluna1 = x.First().Representante,
        Coluna2 = x.Sum(y => y.ValorRepasse).ToString(),
        Coluna3 = x.Sum(y => y.KmRepasse).ToString()
    }).ToList());
于 2019-02-21T17:24:16.190 回答
0

AddRange()返回void，这是您在list. 您不能将其分配给list.

Detalhes = new List<DetalhesExcel>() {
    new DetalhesExcel()
    {
        NumColunaInicial = 23,
        Coluna1 = "Representante",
        Coluna2 = "ValorRepasse",
        Coluna3 = "KmRepasse"
    }
};
Detalhes.AddRange(ocorrencias.Where(x => x.Conclusao != "PRÓPRIO")
        .GroupBy(x => x.Representante)
        .Select(x => new DetalhesExcel
        {
            NumColunaInicial = 23,
            Coluna1 = x.First().Representante,
            Coluna2 = x.Sum(y => y.ValorRepasse).ToString(),
            Coluna3 = x.Sum(y => y.KmRepasse).ToString()
        }).ToList())
于 2019-02-21T17:14:52.917 回答
0

根据您对 Simonare 的回答的评论，您是否尝试过

Detalhes = new List<DetalhesExcel>(ocorrencias.Where(x => x.Conclusao != "PRÓPRIO")
    .GroupBy(x => x.Representante)
    .Select(x => new DetalhesExcel
    {
        NumColunaInicial = 23,
        Coluna1 = x.First().Representante,
        Coluna2 = x.Sum(y => y.ValorRepasse).ToString(),
        Coluna3 = x.Sum(y => y.KmRepasse).ToString()
    }).ToList())
    {
    new DetalhesExcel()
    {
        NumColunaInicial = 23,
        Coluna1 = "Representante",
        Coluna2 = "ValorRepasse",
        Coluna3 = "KmRepasse"
    }
    };

本质上使用基于列表的构造函数中的选定列表

于 2019-02-21T17:29:10.053 回答