C# LinQ按多列分组查找数据差异

// 假设有两个数据集合：source和target
var source = new List<DataItem>
{
    new DataItem { Id = 1, Name = "A", Value = 10 },
    new DataItem { Id = 2, Name = "B", Value = 20 },
    new DataItem { Id = 3, Name = "C", Value = 30 }
};

var target = new List<DataItem>
{
    new DataItem { Id = 1, Name = "A", Value = 10 },
    new DataItem { Id = 2, Name = "B", Value = 25 },
    new DataItem { Id = 4, Name = "D", Value = 40 }
};

// 使用LinQ按多列分组查找数据差异
var diff = source.Concat(target)
                .GroupBy(item => new { item.Id, item.Name })
                .Where(group => group.Count() == 1)
                .Select(group => group.First());

// 输出差异数据
foreach (var item in diff)
{
    Console.WriteLine($"Id: {item.Id}, Name: {item.Name}, Value: {item.Value}");
}