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Infrastructure/Hncore.Infrastructure/EntitiesExtension/CommonEqualityComparer.cs

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+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace Hncore.Infrastructure.EntitiesExtension
+{
+    public class CommonEqualityComparer<T, V> : IEqualityComparer<T>
+    {
+        private Func<T, V> keySelector;
+        private IEqualityComparer<V> comparer;
+
+        public CommonEqualityComparer(Func<T, V> keySelector, IEqualityComparer<V> comparer)
+        {
+            this.keySelector = keySelector;
+            this.comparer = comparer;
+        }
+
+        public CommonEqualityComparer(Func<T, V> keySelector)
+            : this(keySelector, EqualityComparer<V>.Default)
+        { }
+
+        public bool Equals(T x, T y)
+        {
+            return comparer.Equals(keySelector(x), keySelector(y));
+        }
+
+        public int GetHashCode(T obj)
+        {
+            return comparer.GetHashCode(keySelector(obj));
+        }
+    }
+    /// <summary>
+    /// 扩展类
+    /// </summary>
+    public static class DistinctExtensions
+    {
+        public static IEnumerable<T> Distinctx<T, V>(this IEnumerable<T> source, Func<T, V> keySelector)
+        {
+            return source.Distinct(new CommonEqualityComparer<T, V>(keySelector));
+        }
+
+        public static IEnumerable<T> Distinctx<T, V>(this IEnumerable<T> source, Func<T, V> keySelector, IEqualityComparer<V> comparer)
+        {
+            return source.Distinct(new CommonEqualityComparer<T, V>(keySelector, comparer));
+        }
+    } 
+
+}