如何将所有行转换为列？考虑第一列将使用LINQ生成列名。
计算产品是否与product1重复的总和：
我有一个包含以下数据的列表
Product Y1 Y2 Y3 Y4 Y5 Y6 Y7 Y8 Y9 Y10
Product1 1 2 3 4 5 6 7 8 9 10
Product1 2 3 4 5 6 7 8 9 10 11
Product2 2 3 4 5 6 7 8 9 10 11
Product3 3 4 5 6 7 8 9 10 11 12
Product4 4 5 6 7 8 9 10 11 12 13
我需要将输出作为列表
YKey Year Product1 Product2 Product3
Y1 2016 3 2 3 4
Y2 2017 5 3 4 5
Y3 2018 7 4 5 6
Y4 2019 9 5 6 7
Y5 2020 11 6 7 8
Y6 2021 13 7 8 9
Y7 2022 15 8 9 10
Y8 2023 17 9 10 11
Y9 2024 19 10 11 12
Y10 2025 21 11 12 3
我只有4种产品只是为了让您对我的要求有一个清晰的了解，我可能会在固定的20年内每年都有很多产品价值。
年份将从当年开始，如果当前2016年则y1 = 2016年，y2 = 2017年......
下面我提供了list<class>作为示例
private List<Data> CreateColumnData()
{
var list = new List<Data>();
list.Add(new Data() { ProductName = "Product1", Year1 = 1, Year2 = 2, Year3 = 3, Year4 = 4, Year5 = 5, Year6 = 6, Year7 = 7,Year8 = 8,Year9=9,Year10=10});
list.Add(new Data() { ProductName = "Product2", Year1 = 2, Year2 = 3, Year3 = 4, Year4 = 5, Year5 = 6, Year6 = 7, Year7 = 8, Year8 = 9, Year9 = 10, Year10 = 11 });
list.Add(new Data() { ProductName = "Product3", Year1 = 3, Year2 = 4, Year3 = 5, Year4 = 6, Year5 = 7, Year6 = 8, Year7 = 9, Year8 = 10, Year9 = 11, Year10 = 12 });
list.Add(new Data() { ProductName = "Product4", Year1 = 4, Year2 = 5, Year3 = 6, Year4 = 7, Year5 = 8, Year6 = 9, Year7 = 10, Year8 = 11, Year9 = 12, Year10 = 13});
return list;
}
public class Data
{
public string ProductName { get; set; }
public int Year1 { get; set; }
public int Year2 { get; set; }
public int Year3 { get; set; }
public int Year4 { get; set; }
public int Year5 { get; set; }
public int Year6 { get; set; }
public int Year7 { get; set; }
public int Year8 { get; set; }
public int Year9 { get; set; }
public int Year10 { get; set; }
public int Year11 { get; set; }
public int Year12 { get; set; }
public int Year13 { get; set; }
public int Year14 { get; set; }
public int Year15 { get; set; }
}
答案 0 :(得分：0)
我认为Linq没有那么多工作，只有FirstOrDefault。
class Program
{
static void Main()
{
List<Data> src = CreateColumnData();
// Result is a List
List<ResultRow> res = new List<ResultRow>();
foreach (Data dd in src) {
for (int i = 1; i <= 15; i++)
{
String yk = "Y" + i.ToString();
ResultRow r = res.FirstOrDefault(rr => rr.YK == yk);
if (r == null)
{
r = new ResultRow(yk, 2015 + i, 0, 0, 0, 0);
res.Add(r);
}
switch (dd.ProductName)
{
case "Product1": r.Product1 += dd.getYear(i); break;
case "Product2": r.Product2 += dd.getYear(i); break;
case "Product3": r.Product3 += dd.getYear(i); break;
case "Product4": r.Product4 += dd.getYear(i); break;
default: break;
}
}
}
res.All(rr => {
Console.WriteLine(rr.ToString());
return true; });
Console.ReadKey();
}
static private List<Data> CreateColumnData()
{
var list = new List<Data>();
list.Add(new Data() { ProductName = "Product1", Year1 = 1, Year2 = 2, Year3 = 3, Year4 = 4, Year5 = 5, Year6 = 6, Year7 = 7, Year8 = 8, Year9 = 9, Year10 = 10 });
list.Add(new Data() { ProductName = "Product2", Year1 = 2, Year2 = 3, Year3 = 4, Year4 = 5, Year5 = 6, Year6 = 7, Year7 = 8, Year8 = 9, Year9 = 10, Year10 = 11 });
list.Add(new Data() { ProductName = "Product3", Year1 = 3, Year2 = 4, Year3 = 5, Year4 = 6, Year5 = 7, Year6 = 8, Year7 = 9, Year8 = 10, Year9 = 11, Year10 = 12 });
list.Add(new Data() { ProductName = "Product4", Year1 = 4, Year2 = 5, Year3 = 6, Year4 = 7, Year5 = 8, Year6 = 9, Year7 = 10, Year8 = 11, Year9 = 12, Year10 = 13 });
return list;
}
}
// result POCO
public class ResultRow
{
public string YK { get; set; }
public int Year { get; set; }
public int Product1 { get; set; }
public int Product2 { get; set; }
public int Product3 { get; set; }
public int Product4 { get; set; }
public ResultRow (string YK, int Year, int Product1, int Product2, int Product3, int Product4)
{
this.YK = YK;
this.Year = Year;
this.Product1 = Product1;
this.Product2 = Product2;
this.Product3 = Product3;
this.Product4 = Product4;
}
public override string ToString() {
return string.Format("{0},{1},{2},{3},{4},{5}",
YK, Year, Product1, Product2, Product3, Product4);
}
}
public class Data
{
public string ProductName { get; set; }
public int Year1 { get; set; }
public int Year2 { get; set; }
public int Year3 { get; set; }
public int Year4 { get; set; }
public int Year5 { get; set; }
public int Year6 { get; set; }
public int Year7 { get; set; }
public int Year8 { get; set; }
public int Year9 { get; set; }
public int Year10 { get; set; }
public int Year11 { get; set; }
public int Year12 { get; set; }
public int Year13 { get; set; }
public int Year14 { get; set; }
public int Year15 { get; set; }
public int getYear(int i) {
switch (i) {
case 1: return Year1;
case 2: return Year2;
case 3: return Year3;
case 4: return Year4;
case 5: return Year5;
case 6: return Year6;
case 7: return Year7;
case 8: return Year8;
case 9: return Year9;
case 10: return Year10;
case 11: return Year11;
case 12: return Year12;
case 13: return Year13;
case 14: return Year14;
case 15: return Year15;
default: return 0;
}
}
}