38 lines
1.0 KiB
C#
38 lines
1.0 KiB
C#
using System;
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using System.Collections.Generic;
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using System.Linq;
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using System.Text;
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using System.Threading.Tasks;
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namespace IRaCIS.Core.Infrastructure.Extention
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{
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public static class RandomExtensions
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{
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private static Random _random = new Random();
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public static List<T> GetRandomCountList<T>(this List<T> list, int count)
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{
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if (count > list.Count)
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{
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throw new ArgumentException("Sample size cannot be greater than list size.");
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}
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// 使用 Fisher-Yates 洗牌算法来随机选择元素
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List<T> result = list.ToList(); // 复制原始列表，以避免修改原始列表
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int n = result.Count;
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while (n > 1)
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{
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n--;
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int k = _random.Next(n + 1);
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T value = result[k];
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result[k] = result[n];
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result[n] = value;
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}
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// 返回所需数量的元素
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return result.Take(count).ToList();
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}
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}
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}
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