C# 中的 sum 和 Join 与列表泛型

Question

我想收集获得的销售额。

我的课程如下：

 public class PartSell
{
    public string partSellId { get; set; }
    public string partId { get; set; }
}

public class Part
{
    public string partId { get; set; }
    public string Price { get; set; }
}

我的数据如下：

 List<Part> lstPart = new List<Part>()
            {
                new Part{partId="100",Price="150000"},
                 new Part{partId="110",Price="180000"},
                  new Part{partId="120",Price="560000"},
                   new Part{partId="150",Price="970000"}
            };

            List<PartSell> lstPartSell = new List<PartSell>()
             {
                 new PartSell{partId="100",partSellId="1"},
                 new PartSell{partId="110",partSellId="2"},
                 new PartSell{partId="110",partSellId="3"},
                 new PartSell{partId="100",partSellId="4"},
                 new PartSell{partId="100",partSellId="5"},
                 new PartSell{partId="100",partSellId="6"},
                 new PartSell{partId="120",partSellId="7"},
                 new PartSell{partId="100",partSellId="8"}
             };

如何计算 Code 11 的总价

Answer 1

试试这个

var query = from ll in lstPartSell
                    join lp in lstPart on ll.partId equals lp.partId
                    where ll.partId == "110"
                    select int.Parse(lp.Price);
int sum = query.Sum();