Question

 public class SpecialClass
{
    public int property1;
    public ListAttributes attributes = new ListAttributes();
}


 public class ListAttributes
    {
        public List<a> aList = new List<a>();
        public List<b> bList = new List<b>();
        public List<c> cList = new List<c>();
        public List<d> dList = new List<d>();
    }

我有一个SpecialClass个对象列表。我想对它们进行分组，以使具有相同SpecialClass，aList，bList和cList的每个dList对象位于同一组中。

这些列表相等的条件可表示为：

var areEquivalent = !list1.Except(list2).Union(list2.Except(list1)).Any();

换句话说，这些不同的列表应该具有相同的成员，无论它们在列表中的位置如何。

如何使用LINQ完成此操作？（如果它可以表示为lambda表达式，但欢迎使用查询表达式，我将不胜感激）

Answer 1

一种选择是编写自定义library(leaflet) sp <- as(sf_combined, 'Spatial') sf_combined %>% leaflet() %>% addTiles() %>% addPolygons()。这个示例可能会帮助您入门。

EqualityComparer

还可以考虑简化现有的比较，以使用原始问题评论中提到的using System; using System.Collections.Generic; using System.Linq; public class ListAttributesEqualityComparer : IEqualityComparer<ListAttributes> { public bool Equals(ListAttributes x, ListAttributes y) { if (ReferenceEquals(x, y)) return true; if (x == null || y == null) return false; // You should also do null checks on aList etc, but I have left those out for brevity var result = x.aList.Count == y.aList.Count && x.bList.Count == y.bList.Count && x.cList.Count == y.cList.Count && x.dList.Count == y.dList.Count; result = result && !x.aList.Except(y.aList).Union(y.aList.Except(x.aList)).Any(); result = result && !x.bList.Except(y.bList).Union(y.bList.Except(x.bList)).Any(); result = result && !x.cList.Except(y.cList).Union(y.cList.Except(x.cList)).Any(); result = result && !x.dList.Except(y.dList).Union(y.dList.Except(x.dList)).Any(); return result; } public int GetHashCode(ListAttributes obj) { return (obj?.aList?.Distinct()?.Count() ?? 0).GetHashCode(); } } class Program { static void Main(string[] args) { var list = new List<SpecialClass>(); // Populate list here var results = list.GroupBy(g => g.attributes, new ListAttributesEqualityComparer()); Console.ReadLine(); } } public class SpecialClass { public int property1; public ListAttributes attributes = new ListAttributes(); } public class ListAttributes { public List<int> aList = new List<int>(); public List<string> bList = new List<string>(); public List<double> cList = new List<double>(); public List<DateTime> dList = new List<DateTime>(); }。

基于复杂条件的LINQ分组

1 个答案: