组加入Linq C#

组加入Linq C#,c#,linq,C#,Linq,我正在阅读许多网站,以便更好地了解Linq-Group Join var customers = new Customer[] { new Customer{Code = 5, Name = "Sam"}, new Customer{Code = 6, Name = "Dave"}, new Customer{Code = 7, Name = "Julia"}, new Customer{Code = 8, Name = "Sue"} }; // Example

我正在阅读许多网站,以便更好地了解Linq-Group Join

var customers = new Customer[]
{
    new Customer{Code = 5, Name = "Sam"},
    new Customer{Code = 6, Name = "Dave"},
    new Customer{Code = 7, Name = "Julia"},
    new Customer{Code = 8, Name = "Sue"}
};

// Example orders.
var orders = new Order[]
{
    new Order{KeyCode = 5, Product = "Book"},
    new Order{KeyCode = 6, Product = "Game"},
    new Order{KeyCode = 7, Product = "Computer"},
    new Order{KeyCode = 7, Product = "Mouse"},
    new Order{KeyCode = 8, Product = "Shirt"},
    new Order{KeyCode = 5, Product = "Underwear"}
};
        var query = customers.GroupJoin(orders,
          c => c.Code,
          o => o.KeyCode,
          (c, result) => new Result(c.Name, result));//why mention c here??

        // Enumerate results.
        foreach (var result in query)
        {
            Console.WriteLine("{0} bought...", result.Name);
            foreach (var item in result.Collection)
            {
                Console.WriteLine(item.Product);
            }
        }
我不明白为什么它会给出(c,结果)?如果写为(c,o)怎么办


有人能分享一下这方面的想法吗?

这些只是传递给
Func
的参数名称。如果代码更清晰,您可以使用任意名称,即:

        var query = customers.GroupJoin(orders,
        c => c.Code,
        o => o.KeyCode,
        (something1, something2) => new Result(something1.Name, something2));
因为它只是将参数从前面的两个Func传递到最后一个Func,即
Func
,所以在这种情况下
Func

这种情况也一样:

public Result DoStuff(Order nameMeAnyWayYouWant, Customer meToo)
{
    //do stuff here
}
问题代码来自:

我正在添加作者跳过的模型类,如果有人想详细说明,以防dotnetperls.com崩溃:

class Customer
{
    public int Code { get; set; }
    public string Name { get; set; }
}

class Order
{
    public int KeyCode { get; set; }
    public string Product { get; set; }
}

class Result
{
    public string Name { get; set; }
    public IEnumerable<Order> Collection { get; set; }
    public Result(string name, IEnumerable<Order> collection)
    {
        this.Name = name;
        his.Collection = collection;
    }
}
class客户
{
公共整数代码{get;set;}
公共字符串名称{get;set;}
}
阶级秩序
{
公共int键码{get;set;}
公共字符串乘积{get;set;}
}
班级成绩
{
公共字符串名称{get;set;}
公共IEnumerable集合{get;set;}
公共结果(字符串名称,IEnumerable集合)
{
this.Name=Name;
他的收藏=收藏;
}
}

谢谢您的回复。所以你的意思是说var query=customers.GroupJoin(orders,c=>c.Code,o=>o.KeyCode,(c,result)=>newresult(c.Name,result));var query=customers.GroupJoin(orders,c=>c.Code,o=>o.KeyCode,(o,result)=>newresult(o.Name,result));都一样吗?如果是这样,C,O在这里的作用是什么?当然。您可以按自己的方式命名参数。和方法中声明的参数一样,这里只讨论命名。