按属性汇总列表 [英] Summarize list by property

问题描述

我有一个这样的对象列表:

I have a list of objects like this:

List<ClassName> list = new List<ClassName>();
list.Add(new ClassName()
{
    Name = 1,
    Amount = 5
});
list.Add(new ClassName()
{
    Name = 2,
    Amount = 10
});
list.Add(new ClassName()
{
    Name = 1,
    Amount = 20
});
list.Add(new ClassName()
{
    Name = 3,
    Amount = 10
});
list.Add(new ClassName()
{
    Name = 3,
    Amount = 15
});

现在，我想通过属性 Name 总结此列表.结果应为每个 Name 包含一个条目，以及具有相同 Name 的条目的 Amount 之和.因此，这将是预期的结果:

Now I would like to summarize this list by the property Name. The result should contain one entry for every Name and the sum of Amount of the entries with the same Name. So this would be the expected result:

List<ClassName> list = new List<ClassName>();
list.Add(new ClassName()
{
    Name = 1,
    Amount = 25
});
list.Add(new ClassName()
{
    Name = 2,
    Amount = 10
});
list.Add(new ClassName()
{
    Name = 3,
    Amount = 25
});

我该如何存档?

推荐答案

 var lst = list.GroupBy(g = > g.Name).Select(t = > new
 ClassName()
 {
     Amount = t.Sum(s=>s.Amount), Name = t.Key
 }).ToList();

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