Question

我有一个清单：

IList<PIData> list = new List<PIData>()

这将返回如下列表：

Timestamp        | End              | HeaderTitle | Value
=========================================================
12/12/2012 00:00 | 12/12/2012 00:01 | Test1       | 0.23
12/12/2012 00:00 | 12/12/2012 00:01 | Test2       | 0.34
12/12/2012 00:00 | 12/12/2012 00:01 | Test3       | 0.556

这种情况一直持续到有时我会有50-100个不同的HeaderTitles

我需要能够对此进行透视并最终将其写入CSV，其中Row为标题。我知道如何将一个对象转换为CSV，但我很难转动这个列表并希望有人可以提供帮助。

这就是我想要的样子：

Timestamp        | End              | Test1 | Test2 | Test3 | etc
==================================================================
12/12/2012 00:00 | 12/12/2012 00:01 | 0.23  | 0.34  | 0.556
12/12/2012 00:01 | 12/12/2012 00:02 | 0.23  | 0.34  | 0.556
12/12/2012 00:02 | 12/12/2012 00:03 | 0.23  | 0.34  | 0.556

有人能帮助我做这项工作吗？我真的只需要能够将我的列表转移到一个最终将成为CSV文件的新列表......我知道如何在SQL中执行此操作但我不能在这种情况下使用SQL。

Answer 1

以下是我最终做的对我有用的事情：

namespace ConsoleApplication3
{
class Program
{

    internal class PiData
    {
        public string HeaderName { get; set; }
        public DateTime TimeStamp { get; set; }
        public DateTime End { get; set; }
        public double Value { get; set; }
    }

    static void Main(string[] args)
    {
        var PD = new List<PiData>()
        {
            new PiData() { HeaderName="Test1", End = DateTime.Now.AddSeconds(15), TimeStamp = DateTime.Now, Value = 0.01 },
            new PiData() { HeaderName="Testf2", End = DateTime.Now.AddSeconds(15), TimeStamp = DateTime.Now, Value = 0.51 },
            new PiData() { HeaderName="Testff3", End = DateTime.Now.AddSeconds(15), TimeStamp = DateTime.Now, Value = 0.71 },
            new PiData() { HeaderName="Testfsd4", End = DateTime.Now.AddSeconds(15), TimeStamp = DateTime.Now, Value = 0.41 },
            new PiData() { HeaderName="Test1", End = DateTime.Now.AddSeconds(30), TimeStamp = DateTime.Now.AddSeconds(15), Value = 0.01 },
            new PiData() { HeaderName="Testf2", End = DateTime.Now.AddSeconds(30), TimeStamp = DateTime.Now.AddSeconds(15), Value = 0.51 },
            new PiData() { HeaderName="Testff3", End = DateTime.Now.AddSeconds(30), TimeStamp = DateTime.Now.AddSeconds(15), Value = 0.71 },
            new PiData() { HeaderName="Testfsd4", End = DateTime.Now.AddSeconds(30), TimeStamp = DateTime.Now.AddSeconds(15), Value = 0.41 },
        };


    var result2 = PD.Pivot(emp => emp.TimeStamp, emp2 => emp2.HeaderName, lst => lst.Sum(a => a.Value));
    StringBuilder sb = new StringBuilder();

    List<string> columns = new List<string>();
    columns.Add("TimeStamp");
    columns.Add("End");
    foreach (var item in PD.Select(a => a.HeaderName).Distinct())
    {
        columns.Add(item);
    }
    foreach (var item in columns)
    {
        sb.Append(item + ",");
    }
    sb.Remove(sb.Length - 1, 1);
    sb.AppendLine();
    foreach (var row in result2)
    {
        sb.Append(row.Key + "," + row.Key.AddSeconds(10).ToString() + ",");
        foreach (var column in row.Value)
        {
            sb.Append(column.Value + ",");
        }
        sb.Remove(sb.Length - 1, 1);
        sb.AppendLine();
    }
    Console.WriteLine(sb.ToString());
    Console.WriteLine("----"); 

    }
}

public static class LinqExtenions
{

    public static Dictionary<TFirstKey, Dictionary<TSecondKey, TValue>> Pivot<TSource, TFirstKey, TSecondKey, TValue>(this IEnumerable<TSource> source, Func<TSource, TFirstKey> firstKeySelector, Func<TSource, TSecondKey> secondKeySelector, Func<IEnumerable<TSource>, TValue> aggregate)
    {
        var retVal = new Dictionary<TFirstKey, Dictionary<TSecondKey, TValue>>();

        var l = source.ToLookup(firstKeySelector);
        foreach (var item in l)
        {
            var dict = new Dictionary<TSecondKey, TValue>();
            retVal.Add(item.Key, dict);
            var subdict = item.ToLookup(secondKeySelector);
            foreach (var subitem in subdict)
            {
                dict.Add(subitem.Key, aggregate(subitem));
            }
        }

        return retVal;
    }
}


}

将列表转换为数据透视列表

1 个答案: