using System; using System.Collections.Generic; using System.Linq; using System.Linq.Expressions; using System.Threading; using System.Threading.Tasks; namespace IRaCIS.Core.Infrastructure.Extention { public static partial class IEnumerableExtensions { ///// <summary> ///// 按字段去重 ///// </summary> ///// <typeparam name="TSource"></typeparam> ///// <typeparam name="TKey"></typeparam> ///// <param name="source"></param> ///// <param name="keySelector"></param> ///// <returns></returns> //public static IEnumerable<TSource> DistinctBy<TSource, TKey>(this IEnumerable<TSource> source, Func<TSource, TKey> keySelector) //{ // var hash = new HashSet<TKey>(); // return source.Where(p => hash.Add(keySelector(p))); //} /// <summary> /// 添加多个元素 /// </summary> /// <typeparam name="T"></typeparam> /// <param name="this"></param> /// <param name="values"></param> public static void AddRange<T>(this ICollection<T> @this, params T[] values) { foreach (var obj in values) { @this.Add(obj); } } /// <summary> /// 添加符合条件的多个元素 /// </summary> /// <typeparam name="T"></typeparam> /// <param name="this"></param> /// <param name="predicate"></param> /// <param name="values"></param> public static void AddRangeIf<T>(this ICollection<T> @this, Func<T, bool> predicate, params T[] values) { foreach (var obj in values) { if (predicate(obj)) { @this.Add(obj); } } } /// <summary> /// 添加不重复的元素 /// </summary> /// <typeparam name="T"></typeparam> /// <param name="this"></param> /// <param name="values"></param> public static void AddRangeIfNotContains<T>(this ICollection<T> @this, params T[] values) { foreach (T obj in values) { if (!@this.Contains(obj)) { @this.Add(obj); } } } /// <summary> /// 移除符合条件的元素 /// </summary> /// <typeparam name="T"></typeparam> /// <param name="this"></param> /// <param name="where"></param> public static void RemoveWhere<T>(this ICollection<T> @this, Func<T, bool> @where) { foreach (var obj in @this.Where(where).ToList()) { @this.Remove(obj); } } /// <summary> /// 在元素之后添加元素 /// </summary> /// <typeparam name="T"></typeparam> /// <param name="list"></param> /// <param name="condition">条件</param> /// <param name="value">值</param> public static void InsertAfter<T>(this IList<T> list, Func<T, bool> condition, T value) { foreach (var item in list.Select((item, index) => new { item, index }).Where(p => condition(p.item)).OrderByDescending(p => p.index)) { if (item.index + 1 == list.Count) { list.Add(value); } else { list.Insert(item.index + 1, value); } } } /// <summary> /// 在元素之后添加元素 /// </summary> /// <typeparam name="T"></typeparam> /// <param name="list"></param> /// <param name="index">索引位置</param> /// <param name="value">值</param> public static void InsertAfter<T>(this IList<T> list, int index, T value) { foreach (var item in list.Select((v, i) => new { Value = v, Index = i }).Where(p => p.Index == index).OrderByDescending(p => p.Index)) { if (item.Index + 1 == list.Count) { list.Add(value); } else { list.Insert(item.Index + 1, value); } } } /// <summary> /// 转HashSet /// </summary> /// <typeparam name="T"></typeparam> /// <typeparam name="TResult"></typeparam> /// <param name="source"></param> /// <param name="selector"></param> /// <returns></returns> public static HashSet<TResult> ToHashSet<T, TResult>(this IEnumerable<T> source, Func<T, TResult> selector) { var set = new HashSet<TResult>(); set.UnionWith(source.Select(selector)); return set; } /// <summary> /// 遍历IEnumerable /// </summary> /// <param name="objs"></param> /// <param name="action">回调方法</param> /// <typeparam name="T"></typeparam> public static void ForEach<T>(this IEnumerable<T> objs, Action<T> action) { foreach (var o in objs) { action(o); } } /// <summary> /// 异步foreach /// </summary> /// <typeparam name="T"></typeparam> /// <param name="source"></param> /// <param name="maxParallelCount">最大并行数</param> /// <param name="action"></param> /// <param name="cancellationToken"></param> /// <returns></returns> public static async Task ForeachAsync<T>(this IEnumerable<T> source, Func<T, Task> action, int maxParallelCount, CancellationToken cancellationToken = default) { var list = new List<Task>(); foreach (var item in source) { if (cancellationToken.IsCancellationRequested) { return; } list.Add(action(item)); if (list.Count >= maxParallelCount) { await Task.WhenAll(list); list.Clear(); } } await Task.WhenAll(list); } /// <summary> /// 异步foreach /// </summary> /// <typeparam name="T"></typeparam> /// <param name="source"></param> /// <param name="action"></param> /// <returns></returns> public static Task ForeachAsync<T>(this IEnumerable<T> source, Func<T, Task> action, CancellationToken cancellationToken = default) { return ForeachAsync(source, action, source.Count(), cancellationToken); } /// <summary> /// 异步Select /// </summary> /// <typeparam name="T"></typeparam> /// <typeparam name="TResult"></typeparam> /// <param name="source"></param> /// <param name="selector"></param> /// <returns></returns> public static Task<TResult[]> SelectAsync<T, TResult>(this IEnumerable<T> source, Func<T, Task<TResult>> selector) { return Task.WhenAll(source.Select(selector)); } /// <summary> /// 异步Select /// </summary> /// <typeparam name="T"></typeparam> /// <typeparam name="TResult"></typeparam> /// <param name="source"></param> /// <param name="selector"></param> /// <returns></returns> public static Task<TResult[]> SelectAsync<T, TResult>(this IEnumerable<T> source, Func<T, int, Task<TResult>> selector) { return Task.WhenAll(source.Select(selector)); } /// <summary> /// 异步For /// </summary> /// <typeparam name="T"></typeparam> /// <param name="source"></param> /// <param name="selector"></param> /// <param name="maxParallelCount">最大并行数</param> /// <param name="cancellationToken">取消口令</param> /// <returns></returns> public static async Task ForAsync<T>(this IEnumerable<T> source, Func<T, int, Task> selector, int maxParallelCount, CancellationToken cancellationToken = default) { var list = new List<Task>(); int index = 0; foreach (var item in source) { if (cancellationToken.IsCancellationRequested) { return; } list.Add(selector(item, index++)); if (list.Count >= maxParallelCount) { await Task.WhenAll(list); list.Clear(); } } await Task.WhenAll(list); } /// <summary> /// 异步For /// </summary> /// <typeparam name="T"></typeparam> /// <param name="source"></param> /// <param name="selector"></param> /// <param name="cancellationToken">取消口令</param> /// <returns></returns> public static Task ForAsync<T>(this IEnumerable<T> source, Func<T, int, Task> selector, CancellationToken cancellationToken = default) { return ForAsync(source, selector, source.Count(), cancellationToken); } /// <summary> /// 取最大值 /// </summary> /// <typeparam name="TSource"></typeparam> /// <typeparam name="TResult"></typeparam> /// <param name="source"></param> /// <param name="selector"></param> /// <returns></returns> public static TResult MaxOrDefault<TSource, TResult>(this IQueryable<TSource> source, Expression<Func<TSource, TResult>> selector) => source.Select(selector).DefaultIfEmpty().Max(); /// <summary> /// 取最大值 /// </summary> /// <typeparam name="TSource"></typeparam> /// <typeparam name="TResult"></typeparam> /// <param name="source"></param> /// <param name="selector"></param> /// <param name="defaultValue"></param> /// <returns></returns> public static TResult MaxOrDefault<TSource, TResult>(this IQueryable<TSource> source, Expression<Func<TSource, TResult>> selector, TResult defaultValue) => source.Select(selector).DefaultIfEmpty(defaultValue).Max(); /// <summary> /// 取最大值 /// </summary> /// <typeparam name="TSource"></typeparam> /// <param name="source"></param> /// <returns></returns> public static TSource MaxOrDefault<TSource>(this IQueryable<TSource> source) => source.DefaultIfEmpty().Max(); /// <summary> /// 取最大值 /// </summary> /// <typeparam name="TSource"></typeparam> /// <param name="source"></param> /// <param name="defaultValue"></param> /// <returns></returns> public static TSource MaxOrDefault<TSource>(this IQueryable<TSource> source, TSource defaultValue) => source.DefaultIfEmpty(defaultValue).Max(); /// <summary> /// 取最大值 /// </summary> /// <typeparam name="TSource"></typeparam> /// <typeparam name="TResult"></typeparam> /// <param name="source"></param> /// <param name="selector"></param> /// <param name="defaultValue"></param> /// <returns></returns> public static TResult MaxOrDefault<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector, TResult defaultValue) => source.Select(selector).DefaultIfEmpty(defaultValue).Max(); /// <summary> /// 取最大值 /// </summary> /// <typeparam name="TSource"></typeparam> /// <typeparam name="TResult"></typeparam> /// <param name="source"></param> /// <param name="selector"></param> /// <returns></returns> public static TResult MaxOrDefault<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector) => source.Select(selector).DefaultIfEmpty().Max(); /// <summary> /// 取最大值 /// </summary> /// <typeparam name="TSource"></typeparam> /// <param name="source"></param> /// <returns></returns> public static TSource MaxOrDefault<TSource>(this IEnumerable<TSource> source) => source.DefaultIfEmpty().Max(); /// <summary> /// 取最大值 /// </summary> /// <typeparam name="TSource"></typeparam> /// <param name="source"></param> /// <param name="defaultValue"></param> /// <returns></returns> public static TSource MaxOrDefault<TSource>(this IEnumerable<TSource> source, TSource defaultValue) => source.DefaultIfEmpty(defaultValue).Max(); /// <summary> /// 取最小值 /// </summary> /// <typeparam name="TSource"></typeparam> /// <typeparam name="TResult"></typeparam> /// <param name="source"></param> /// <param name="selector"></param> /// <returns></returns> public static TResult MinOrDefault<TSource, TResult>(this IQueryable<TSource> source, Expression<Func<TSource, TResult>> selector) => source.Select(selector).DefaultIfEmpty().Min(); /// <summary> /// 取最小值 /// </summary> /// <typeparam name="TSource"></typeparam> /// <typeparam name="TResult"></typeparam> /// <param name="source"></param> /// <param name="selector"></param> /// <param name="defaultValue"></param> /// <returns></returns> public static TResult MinOrDefault<TSource, TResult>(this IQueryable<TSource> source, Expression<Func<TSource, TResult>> selector, TResult defaultValue) => source.Select(selector).DefaultIfEmpty(defaultValue).Min(); /// <summary> /// 取最小值 /// </summary> /// <typeparam name="TSource"></typeparam> /// <param name="source"></param> /// <returns></returns> public static TSource MinOrDefault<TSource>(this IQueryable<TSource> source) => source.DefaultIfEmpty().Min(); /// <summary> /// 取最小值 /// </summary> /// <typeparam name="TSource"></typeparam> /// <param name="source"></param> /// <param name="defaultValue"></param> /// <returns></returns> public static TSource MinOrDefault<TSource>(this IQueryable<TSource> source, TSource defaultValue) => source.DefaultIfEmpty(defaultValue).Min(); /// <summary> /// 取最小值 /// </summary> /// <typeparam name="TSource"></typeparam> /// <typeparam name="TResult"></typeparam> /// <param name="source"></param> /// <param name="selector"></param> /// <returns></returns> public static TResult MinOrDefault<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector) => source.Select(selector).DefaultIfEmpty().Min(); /// <summary> /// 取最小值 /// </summary> /// <typeparam name="TSource"></typeparam> /// <typeparam name="TResult"></typeparam> /// <param name="source"></param> /// <param name="selector"></param> /// <param name="defaultValue"></param> /// <returns></returns> public static TResult MinOrDefault<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector, TResult defaultValue) => source.Select(selector).DefaultIfEmpty(defaultValue).Min(); /// <summary> /// 取最小值 /// </summary> /// <typeparam name="TSource"></typeparam> /// <param name="source"></param> /// <returns></returns> public static TSource MinOrDefault<TSource>(this IEnumerable<TSource> source) => source.DefaultIfEmpty().Min(); /// <summary> /// 取最小值 /// </summary> /// <typeparam name="TSource"></typeparam> /// <param name="source"></param> /// <param name="defaultValue"></param> /// <returns></returns> public static TSource MinOrDefault<TSource>(this IEnumerable<TSource> source, TSource defaultValue) => source.DefaultIfEmpty(defaultValue).Min(); ///// <summary> ///// 标准差 ///// </summary> ///// <typeparam name="T"></typeparam> ///// <param name="source"></param> ///// <param name="selector"></param> ///// <returns></returns> //public static TResult StandardDeviation<T, TResult>(this IEnumerable<T> source, Func<T, TResult> selector) where TResult : IConvertible //{ // return StandardDeviation(source.Select(t => selector(t).ConvertTo<double>())).ConvertTo<TResult>(); //} ///// <summary> ///// 标准差 ///// </summary> ///// <typeparam name="T"></typeparam> ///// <param name="source"></param> ///// <returns></returns> //public static T StandardDeviation<T>(this IEnumerable<T> source) where T : IConvertible //{ // return StandardDeviation(source.Select(t => t.ConvertTo<double>())).ConvertTo<T>(); //} /// <summary> /// 标准差 /// </summary> /// <param name="source"></param> /// <returns></returns> public static double StandardDeviation(this IEnumerable<double> source) { double result = 0; int count = source.Count(); if (count > 1) { double avg = source.Average(); double sum = source.Sum(d => (d - avg) * (d - avg)); result = Math.Sqrt(sum / count); } return result; } /// <summary> /// 随机排序 /// </summary> /// <typeparam name="T"></typeparam> /// <param name="source"></param> /// <returns></returns> public static IOrderedEnumerable<T> OrderByRandom<T>(this IEnumerable<T> source) { return source.OrderBy(_ => Guid.NewGuid()); } /// <summary> /// 序列相等 /// </summary> /// <typeparam name="T"></typeparam> /// <param name="first"></param> /// <param name="second"></param> /// <param name="condition"></param> /// <returns></returns> public static bool SequenceEqual<T>(this IEnumerable<T> first, IEnumerable<T> second, Func<T, T, bool> condition) { if (first is ICollection<T> source1 && second is ICollection<T> source2) { if (source1.Count != source2.Count) { return false; } if (source1 is IList<T> list1 && source2 is IList<T> list2) { int count = source1.Count; for (int index = 0; index < count; ++index) { if (!condition(list1[index], list2[index])) { return false; } } return true; } } using IEnumerator<T> enumerator1 = first.GetEnumerator(); using IEnumerator<T> enumerator2 = second.GetEnumerator(); while (enumerator1.MoveNext()) { if (!enumerator2.MoveNext() || !condition(enumerator1.Current, enumerator2.Current)) { return false; } } return !enumerator2.MoveNext(); } /// <summary> /// 序列相等 /// </summary> /// <typeparam name="T1"></typeparam> /// <typeparam name="T2"></typeparam> /// <param name="first"></param> /// <param name="second"></param> /// <param name="condition"></param> /// <returns></returns> public static bool SequenceEqual<T1, T2>(this IEnumerable<T1> first, IEnumerable<T2> second, Func<T1, T2, bool> condition) { if (first is ICollection<T1> source1 && second is ICollection<T2> source2) { if (source1.Count != source2.Count) { return false; } if (source1 is IList<T1> list1 && source2 is IList<T2> list2) { int count = source1.Count; for (int index = 0; index < count; ++index) { if (!condition(list1[index], list2[index])) { return false; } } return true; } } using IEnumerator<T1> enumerator1 = first.GetEnumerator(); using IEnumerator<T2> enumerator2 = second.GetEnumerator(); while (enumerator1.MoveNext()) { if (!enumerator2.MoveNext() || !condition(enumerator1.Current, enumerator2.Current)) { return false; } } return !enumerator2.MoveNext(); } /// <summary> /// 对比两个集合哪些是新增的、删除的、修改的 /// </summary> /// <typeparam name="T1"></typeparam> /// <typeparam name="T2"></typeparam> /// <param name="olds"></param> /// <param name="news"></param> /// <param name="key1Selector">对比因素属性</param> /// <param name="key2Selector">对比因素属性</param> /// <returns></returns> public static (List<T2> adds, List<T1> remove, List<T1> updates) CompareChanges<T1, T2>(this IEnumerable<T1> olds, IEnumerable<T2> news, Func<T1, object> key1Selector, Func<T2, object> key2Selector) { return (news.Where(c => olds.All(m => key1Selector(m) != key2Selector(c))).ToList(), olds.Where(m => news.All(c => key2Selector(c) != key1Selector(m))).ToList(), olds.Where(m => news.Any(c => key1Selector(m) == key2Selector(c))).ToList()); } /// <summary> /// 对比两个集合哪些是新增的、删除的、修改的 /// </summary> /// <typeparam name="T"></typeparam> /// <param name="olds"></param> /// <param name="news"></param> /// <param name="keySelector">对比因素属性</param> /// <returns></returns> public static (List<T> adds, List<T> remove, List<T> updates) CompareChanges<T>(this IEnumerable<T> olds, IEnumerable<T> news, Func<T, object> keySelector) { return (news.Where(c => olds.All(m => keySelector(m) != keySelector(c))).ToList(), olds.Where(m => news.All(c => keySelector(c) != keySelector(m))).ToList(), olds.Where(m => news.Any(c => keySelector(m) == keySelector(c))).ToList()); } } }