List hashset and remove items from it

You just need to use RemoveWhere () with the corresponding predicate function.

, ( , " " ), . , , , .

, ​​ HashSet undefined, , , true false .

[EDIT] .

using System;
using System.Collections.Generic;

namespace Demo
{
    public class Program
    {
        [STAThread]
        private static void Main(string[] args)
        {
            var hashSet = new HashSet<int> {4, 0, 6, -1, 23, -8, 14, 12, -9, 5, 2};
            var itemProcessor = new ItemProcessor();

            hashSet.RemoveWhere(itemProcessor.Process);

            Console.WriteLine("Max = {0}, Min = {1}", itemProcessor.Max, itemProcessor.Min);
            Console.WriteLine("\nHashSet contents:");

            foreach (int number in hashSet)
            {
                Console.WriteLine(number);
            }
        }
    }

    public sealed class ItemProcessor
    {
        private int max = int.MinValue;
        private int min = int.MaxValue;

        // Removes all negative numbers and calculates max and min values.

        public bool Process(int item)
        {
            max = Math.Max(item, max);
            min = Math.Min(item, min);

            return (item < 0);
        }

        public int Max { get { return max; } }
        public int Min { get { return min; } }
    }
}