如何使用LINQ合并来自多个IEnumerable <T>的结果

Question

我可以有多个(最多5个),IEnumerable<ResortSupplier>并希望IEnumerable<ResortSupplier>通过SupplierCode 将它们合并为单个分组.我的对象看起来像这样:

这是我的对象:

[Serializable]
public class ResortSupplier
{
    public string SupplierCode { get; set; }
    public IList<Product> ResortProducts { get; set; }
}

[Serializable]
public class Product
{
    public string Code { get; set; }
    //Other fields... 
    public IList<PerPricing> PricingDetail { get; set; }
}

[Serializable]
public class PerPricing
{
    //Other fields..
    public decimal? Price { get; set; }
    public Error PricingError { get; set; }
}

多个IEnumerable中的数据可能如下所示:

----------------------------------------
IEnumerable<ResortSupplier> - 1

Hyatt Resort
  Standard Room
    PricingDetail-1
  Superior Room         
    PricingDetail-1

Sandals Resort
  Standard Room
    PricingDetail-1
  Delux Room            
    PricingDetail-1

----------------------------------------
IEnumerable<ResortSupplier> - 2

Hyatt Resort
  Standard Room
    PricingDetail-2
  Superior Room         
    PricingDetail-2
  One Bed Room Suit
    PricingDetail-2

Sandals Resort
  Standard Room
    PricingDetail-2
  Honeymoon Suit            
    PricingDetail-2
----------------------------------------
IEnumerable<ResortSupplier> - 3
.....
----------------------------------------
IEnumerable<ResortSupplier> - 4
.....
----------------------------------------
IEnumerable<ResortSupplier> - 5
.....
----------------------------------------

我的综合结果应包含:

IEnumerable<ResortSupplier> - Consolidated

Hyatt Resort
  Standard Room
    PricingDetail-1
    PricingDetail-2
  Superior Room         
    PricingDetail-1
    PricingDetail-2
  Bed Room Suit
    PricingDetail-2

Sandals Resort
  Standard Room
    PricingDetail-1
    PricingDetail-2
  Delux Room            
    PricingDetail-1
  Honeymoon Suit            
    PricingDetail-2

----------------------------------------

处理这个问题的最佳方法是什么？我尝试了简单的IEnumerable.Union和GroupBy子句,但没有得到我想要的结果.

Answer 1

我想你想要这样的东西：

// You can construct this with an array if it isn't already in this form.
IEnumerable<IEnumerable<ResortSupplier>> supplierLists = ...

var query = from suppliers in supplierLists
            from supplier in suppliers
            group supplier by supplier.SupplierCode into g

            let products = g.SelectMany(s => s.ResortProducts)
                            .GroupBy(p => p.Code)
                            .Select(prodGroup => new Product
                                    {
                                       Code = prodGroup.Key,
                                       PricingDetail = prodGroup
                                                       .SelectMany(p => p.PricingDetail)
                                                       .ToList()
                                    })

            select new ResortSupplier
            {
                SupplierCode  = g.Key, 
                ResortProducts = products.ToList()                              
            };

但这确实是一个看起来很可怕的查询。我强烈建议将查询的不同组成部分分解为单独的（命名良好的）方法。