Question

我有一个对象列表，可能包含也可能不包含具有相同属性的对象。如果存在重复项（例如具有相同属性值的对象），我想通过平均它们的值来组合它们。

例如（实际对象可以有超过3个属性）：

var myList = List<Attribute>(){
    new Attribute(){Id = "Score", Label = "Score", Rating = 4.5},
    new Attribute(){Id = "Price", Label = "Retail Price", Rating = 14.99},
    new Attribute(){Id = "Score", Label = "Score", Rating = 3.5},
    new Attribute(){Id = "Value", Label = "Overall Value", Rating = 5}
}

我想将两个属性与属性Id =“Score”结合起来，并取两个等级的平均值得到类似的结果：

var myList = List<Attribute>(){
    new Attribute(){Id = "Score", Label = "Score", Rating = 4.0},
    new Attribute(){Id = "Price", Label = "Retail Price", Rating = 14.99},
    new Attribute(){Id = "Value", Label = "Overall Value", Rating = 5}
}

我相信我需要使用GroupBy，Select和Average这样的伪代码myList.GroupBy(x => x.Id).Select(x=> new{ x.Id, x.Label, x.Average(x=>x.Rating)} )

有人能指出我正确的方向吗？非常感谢。

Answer 1

不确定Label属性是什么，它总是一样吗？ Nevertheles，它应该看起来像：

var output = myList.GroupBy(x => x.Id,
                            (key, values) => new Attribute() 
                            {
                               Id = key,
                               Label = values.First().Label,
                               Rating = values.Average(v => v.Rating)
                            })
                    .ToList();

结合重复和平均值

1 个答案: