使用LINQ或其他模块在C#中连接两个查询的结果

var query = from item1 in query1
            join item2 in query2 on item1.Key equals item2.Key
            select new { item1, item2 };

var query = from item1 in query1
            join item2 in query2 on item1.Key equals item2.Key into joined
            from item2 in joined.DefaultIfEmpty()
            select new { item1, item2 };

var query = from item2 in query2
            join item1 in query1 on item2.Key equals item1.Key into joined
            from item1 in joined.DefaultIfEmpty()
            select new { item1, item2 };

var query = from item1 in query1
            join item2 in query2 on item1.Key equals item2.Key into joined
            from item2 in joined.DefaultIfEmpty()
            select new { item1, item2 }
        .Union
        (
            from item2 in query2
            join item1 in query1 on item2.Key equals item1.Key into joined
            from item1 in joined.DefaultIfEmpty()
            select new { item1, item2 }
        );