在复杂对象中按列表排序答案

【问题标题】：Order by list in complex object在复杂对象中按列表排序
【发布时间】：2016-09-27 09:11:24
【问题描述】：

我有两门课：

public class Customer
{
    public string FirstName { get; set; }

    public string LastName { get; set; }

    public List<Product> Product { get; set; }
}

public class Product
{
    public int ProductNumber { get; set; }

    public string ProductColor { get; set; }
}

还有一个例子：

Customer Cus = new Customer()
{
    FirstName = "FirstName1",
    LastName = "LastName1",
    Product = new List<Product>
    {
        new Product()
        {
            ProductColor = "ProductColor12",
            ProductNumber = 12
        },
        new Product()
        {
            ProductColor = "ProductColor11",
            ProductNumber = 11
        }
    }
};

我想对产品列表进行排序并获取一个客户，其产品列表按ProductNumber排序

如何做到这一点？

【问题讨论】：

How to Sort a List<T> by a property in the object的可能重复

标签： c# linq sorting

【解决方案1】：

Cus.Product = Cus.Product.OrderBy(p => p.ProductNumber).ToList();

【讨论】：

【解决方案2】：

产品类应该在 IComparable 接口中实现 CompareTo 方法

【讨论】：

【解决方案3】：

试试这个

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;


namespace ConsoleApplication2
{
    class Program
    {
        static void Main(string[] args)
        {
            List<Customer> customers = new List<Customer>();
            Customer Cus = new Customer()
            {
                FirstName = "FirstName1",
                LastName = "LastName1",
                Product = new List<Product> {
                    new Product()
                    {
                        ProductColor = "ProductColor12",
                        ProductNumber = 12
                    },
                    new Product()
                    {
                        ProductColor = "ProductColor11",
                        ProductNumber = 11
                    }
                }
            };
            customers.Add(Cus);

            var results = customers.OrderBy(x => x.LastName).ThenBy(y => y.FirstName).Select(z => z.Product.OrderBy(a => a.ProductNumber)).ToList();

        }
    }
    public class Customer
    {
        public string FirstName { get; set; }

        public string LastName { get; set; }

        public List<Product> Product { get; set; }
    }

    public class Product
    {
        public int ProductNumber { get; set; }

        public string ProductColor { get; set; }
    }
}

【讨论】：