对 List<> 中的值求和并删除重复项 [重复项]

Question

我想检查列表中的重复值并将价格汇总在一起。

按照下面的示例进行操作。

例如

var list = new List<Item>();
list.Add(new Item() { code= "521523", text= "cookie", price= 5});
list.Add(new Item() { code= "521523", text= "donut", price= 20 });
list.Add(new Item() { code= "521524", text= "coffee", price= 15 });
list.Add(new Item() { code= "521524", text= "water", price= 16 });
list.Add(new Item() { code= "521525", text= "other", price= 16 });

结果

code= "521523", text= "cookie", price= 25
code= "521524", text= "coffee", price= 31
code= "521525", text= "other", price= 16

Answer 1

你可以使用GroupBy:

list = list 
   .GroupBy(i => i.code)
   .Select(g => new Item
    { 
       code = g.Key, 
       text = String.Join(",", g.Select(i => i.text)), // join better than taking First()
       price = g.Sum(i => i.price)
    })
    .ToList();