Question

我有很多对象，每个对象都有一个数组，我想用数组中的值对这些对象进行分组，所以从概念上看它们如下：

var objects = new []{
  object1 = new object{
    elements = []{1,2,3}
  },
  object2 = new object{
    elements = []{1,2}
  },
  object3 = new object{
    elements = []{1,2}
  },
  object4 = new object{
    elements = null
  }
}

分组后

：

group1: object1
group2: object2,object3
group3: object4

我试过的一些事情：实际课程：

    public class RuleCms
        {
            public IList<int> ParkingEntitlementTypeIds { get; set; }
        }


var rules = new List<RuleCms>()
        {
            new RuleCms()
            {
                ParkingEntitlementTypeIds = new []{1,2}
            },
            new RuleCms()
            {
                ParkingEntitlementTypeIds = new []{1,2}
            },
            new RuleCms()
            {
                ParkingEntitlementTypeIds = new []{1}
            },
            new RuleCms()
            {
                ParkingEntitlementTypeIds = null
            }
        };

var firstTry = rules.GroupBy(g => new { entitlementIds = g.ParkingEntitlementTypeIds, rules = g })
                    .Where(x => x.Key.entitlementIds !=null && x.Key.entitlementIds.Equals(x.Key.rules.ParkingEntitlementTypeIds));

var secondTry =
            rules.GroupBy(g => new { entitlementIds = g.ParkingEntitlementTypeIds ?? new List<int>(), rules = g })
                .GroupBy(x => !x.Key.entitlementIds.Except(x.Key.rules.ParkingEntitlementTypeIds ?? new List<int>()).Any());

Answer 1

您可以使用IEqualityComparer课程。这是代码：

LinearLayout

然后

class MyClass
{
    public string Name { get; set; }
    public int[] Array { get; set; }
}

class ArrayComparer : IEqualityComparer<int[]>
{
    public bool Equals(int[] x, int[] y)
    {
        return x.SequenceEqual(y);
    }

    public int GetHashCode(int[] obj)
    {
        return string.Join(",", obj).GetHashCode();
    }
}

Answer 2

对于真正与您的示例一样简单的简单数据，您可以这样做：

.GroupBy(x => string.Join("|", x.IDS))
.Select(x => new 
             {
                  IDS = x.Key.Split('|').Where(s => s != string.Empty).ToArray(),
                  Count = x.Count()
             });

Linq - 通过使用数组属性中的元素进行分组

2 个答案: