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CSharp · Console

/Program.cs

using System;
using System.Collections;
using System.Collections.Generic;
using System.Linq;

public class Program
{
	public static void Main()
	{
		var startDate = new DateTime(2015, 7, 1);
		var endDate = new DateTime(2015, 9, 1);
		var workDates = Enumerable.Range(0, (int)(endDate - startDate).TotalDays + 1)
			.Select(i => startDate.AddDays(i))
			.Where(date => (date.DayOfWeek != DayOfWeek.Saturday && date.DayOfWeek != DayOfWeek.Sunday))
			.Select(i => i);
		
		
		var display = workDates
			.GroupAdjacentBy((x, y) => x.AddDays(1) == y)
			.Select(g => string.Format("Start: {0:dd/MMM/yyyy} End: {1:dd/MMM/yyy}", g.First(), g.Last()));
		
		foreach (var displayString in display)
		{
			Console.WriteLine(displayString);
		}
	}
}

public static class IEnumerableExtension
{
	public static IEnumerable<IEnumerable<T>> GroupAdjacentBy<T>(
		this IEnumerable<T> source, Func<T, T, bool> predicate)
	{
		using (var e = source.GetEnumerator())
		{
			if (e.MoveNext())
			{
				var list = new List<T> { e.Current };
				var pred = e.Current;
				while (e.MoveNext())
				{
					if (predicate(pred, e.Current))
					{
						list.Add(e.Current);
					}
					else
					{
						yield return list;
						list = new List<T> { e.Current };
					}
					pred = e.Current;
				}
				yield return list;
			}
		}
	}
}