Question

尝试对两个属性进行linq连接，其中两个属性的名称互不相同。

join子句中的表达式之一的类型不正确加入通话的类型推断失败

这是代码

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

namespace linq2
{
    class Program
    {
        static void Main(string[] args)
        {
            List<MyClass1> list1 = new List<MyClass1>() { new MyClass1() { thing1 = "hello", thing2 = "world" } };
            List<MyClass2> list2 = new List<MyClass2>() { new MyClass2() { thing3 = "hello", thing4 = "world" } };

            var bothLists = from l1 in list1
                            join l2 in list2 on new { l1.thing1, l1.thing2 } equals new { l2.thing3, l2.thing4 }
                            select new
                            {
                                thing1 = l1.thing1,
                                thing2 = l1.thing2
                            };

            Console.WriteLine("Hello World!");
        }
    }

    public class MyClass1
    {
        public string thing1 { get; set; }
        public string thing2 { get; set; }
    }

    public class MyClass2
    {
        public string thing3 { get; set; }
        public string thing4 { get; set; }
    }
}

Answer 1

您只需在查询的join子句中重命名属性即可：

from l1 in list1
join l2 in list2 
on new { a = l1.thing1, b = l1.thing2 } equals new { a= l2.thing3, b = l2.thing4 }
select new
{
      thing1 = l1.thing1,
      thing2 = l1.thing2
 };

这将解决问题。

c＃linq连接具有不同名称的多个属性

1 个答案: