QQ：由poco集团不工作 [英] QQ: Group by poco not working

问题描述

我有一个产品数组，一个自定义POCO。其中一些产品指的是同一个产品。一些将具有TariffUnrestricted价格，另一个将具有StandingChargePenceDay。我需要将它们合并在一起。



我正在尝试将产品组合在一起，然后选择每个产品的密钥和值。我认为代码会更好地解释：

Hi,

I have an array of Products, a custom POCO. Some of these products refer to the same item. Some will have the TariffUnrestricted price and another will have the StandingChargePenceDay . I need to merge these together.

I am trying to group the products together, then select out the key and the values for each product. I think the code will explain better:

public override Product[] Import(string path, Func<Worksheet, bool> worksheetSelector = null)
{
    Product[] products = base.Import(path, worksheetSelector);

    var groups = products.GroupBy(p => new Product
    {
        PlanName = p.PlanName,
        RateType = p.RateType,
        ContractDuration = p.ContractDuration,
        Duration = p.Duration,
        TariffDescription = p.TariffDescription,
        //TariffUnrestricted = p.TariffUnrestricted,
        //StandingChargePenceDay = p.StandingChargePenceDay
    });

    products = groups.Select(g =>
    {
        Product product = g.Key;
        product.TariffUnrestricted = g.Max(p => p.TariffUnrestricted);
        product.StandingChargePenceDay = g.Max(p => p.StandingChargePenceDay);
        return product;
    }).ToArray();

    return products;
}

物品不合并。组的数量始终与产品数量相同（1：1）。



我尝试制作产品IComparable< Product> ;,IComparer< Product> ;, IEquatable<产品与GT;但是什么都没有用？



我的google-fu是一周。我找不到正确的用语：C



我做错了什么？



谢谢

Andy

The items do not merge. The number of groups is always the same as the number of products (1:1).

I tried making the Product IComparable<Product>, IComparer<Product>, IEquatable<Product> but nothing works?

My google-fu is week. I cannot find the correct terms :C

What am I doing wrong?

Thanks
Andy

推荐答案

为什么要尝试按新产品分组？所有这一切都是尝试按参考值本身进行分组，不是吗？这将解释组和产品之间的1：1相关性。 ：笑：

你不想要这样的东西：

Why are you trying to group by a new product? All that will do is attempt to group by the reference value itself, won't it? Which would explain the 1:1 correlation between groups and products. :laugh:
Don't you want something like:

var groups = products.GroupBy(p => p.TariffDescription);

或类似的？



[edit]

快速测试：

or similar?

[edit]
A quick test:

public class MyClass
    {
    public int Value { get; set; }
    public string Name { get; set; }
    }

和

And

List<MyClass> list = new List<MyClass>();
MyClass a = new MyClass() { Value = 1, Name = "A" };
MyClass b = new MyClass() { Value = 1, Name = "B" };
MyClass c = new MyClass() { Value = 2, Name = "C" };
MyClass d = new MyClass() { Value = 2, Name = "D" };
MyClass e = new MyClass() { Value = 3, Name = "E" };
list.Add(a);
list.Add(b);
list.Add(c);
list.Add(d);
list.Add(e);
var g1 = list.GroupBy(m => m.Value);
var g2 = list.GroupBy(m => new MyClass { Value = m.Value, Name = m.Name });
Console.WriteLine(g1.Count() + ":" + g2.Count());

给出3：5



添加IEquatable接口不会改变：

Gives "3:5"

Adding the IEquatable interface doesn't change that either:

public class MyClass : IEquatable<MyClass>
    {
    public int Value { get; set; }
    public string Name { get; set; }
    public bool Equals(MyClass other)
        {
        return Value == other.Value;
        }
    }

我仍然得到3：5



[/ edit]

I still get 3:5

[/edit]

这篇关于QQ：由poco集团不工作的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！