MaxCountEnumerator.cs

using System;
using System.Collections;
using System.Threading.Tasks;
 
namespace Waher.Script.Persistence.SQL.Enumerators
{
    public class MaxCountEnumerator : IResultSetEnumerator
    {
        private readonly IResultSetEnumerator e;
        private readonly int count0;
        private int count;
 
        public MaxCountEnumerator(IResultSetEnumerator ItemEnumerator, int Count)
        {
            this.e = ItemEnumerator;
            this.count = this.count0 = Count;
        }
 
        public object Current => this.e.Current;
    
        public void Dispose()
        {
            this.e.Dispose();
        }
 
        public bool MoveNext()
        {
            return this.MoveNextAsync().Result;
        }
 
        public async Task<bool> MoveNextAsync()
        {
            if (this.count <= 0 || !await this.e.MoveNextAsync())
                return false;
 
            this.count--;
 
            return true;
        }
 
        public void Reset()
        {
            this.count = this.count0;
            this.e.Reset();
        }
    }
}