如何比较两个列表并返回3个分类列表 [英] How do I compare two lists and return 3 categoried lists

问题描述

我有两个列表具有相同的属性，我想比较新旧数据库之间的数据

i have tow lists have the same properties and i want to compare the data between old and new DB

List<srsEmployee> srsEmps = db.srsEmployees.ToList(); //from old DB
    List<destEmployee> destEmps = db2.destEmployees.ToList(); //from new DBs

i需要在视图中显示三个列表

1.新增员工

2.Deleted Employee

3.Common Employee

所以任何人都可以帮助我吗？



此查询我写的但结果不对



我尝试过：

i need Three list shown in the view
1.Newly Added Employee
2.Deleted Employee
3.Common Employee
so anyone can help me ?

this query what i wrote but the result isn't right

What I have tried:

    var Common = destEmps.Where(n => srsEmps.Any(o => o.EmpCode == n.EmpCode)).ToList();
    var Deleted = srsEmps.Where(o => !destEmps.Any(n => n.EmpCode == o.EmpCode)).ToList();
    var NewlyAdded = destEmps.Where(n => !srsEmps.Any(o => o.EmpCode == n.EmpCode)).ToList();
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推荐答案

我并不自称善于使用LINQ，但确实给了它一个机会概念证明，它可以按照我的意图运作。



这不是100％的解决方案，但应该是一个很好的基础使用。

I do not profess to being adept with LINQ, but did give it a shot with this Proof-of-Concept and it works as I would intend it to.

It is not a 100% solution for you as is, but should be a good base to work with.

namespace ProofOfConcept {
	public class Employee {
		public int EmpCode { get; set; }
		public string EmpName { get; set; }

		public Employee() { }
		public Employee(int Code, string Name) {
			EmpCode = Code;
			EmpName = Name;
		}
	}

	class Program {
		static void Main(string[] args) {

			List<Employee> srsEmps = new List<Employee>();
				srsEmps.Add(new Employee(1, "Me"));
				srsEmps.Add(new Employee(2, "You"));

			List<Employee> destEmps = new List<Employee>();
				destEmps.Add(new Employee(2, "You"));
				destEmps.Add(new Employee(3, "Someone Else"));

			var Deleted =
				from s in srsEmps
				where !(from d in destEmps select d.EmpCode).Contains(s.EmpCode)
				select s;

			var Common =
				from s in srsEmps
				where (from d in destEmps select d.EmpCode).Contains(s.EmpCode)
				select s;

			var NewlyAdded =
				from d in destEmps
				where !(from s in srsEmps select s.EmpCode).Contains(d.EmpCode)
				select d;

			foreach (Employee d in Deleted) {
				Console.WriteLine("Deleted = " + d.EmpName);
			}
			foreach (Employee c in Common) {
				Console.WriteLine("Common = " + c.EmpName);
			}
			foreach (Employee n in NewlyAdded) {
				Console.WriteLine("New = " + n.EmpName);
			}

			Console.WriteLine("Press any key to continue");
			Console.ReadLine();
		}
	}
}

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