/// <summary>Provides a set of methods and properties that you can use to accurately measure elapsed time.</summary>  
public class Stopwatch  
{  
    #region SafeNativeMethods  
    [DllImport("kernel32.dll")]  
    private static extern bool QueryPerformanceFrequency(out long lpFrequency);  
    [DllImport("kernel32.dll")]  
    private static extern bool QueryPerformanceCounter(out long lpPerformanceCount);  
    #endregion //SafeNativeMethods  
    #region Public Fields          
    /// <summary>Gets the frequency of the timer as the number of ticks per second. This field is read-only.</summary>  
    public static readonly long Frequency;  
      
    /// <summary>Indicates whether the timer is based on a high-resolution performance counter. This field is read-only.</summary>  
    public static readonly bool IsHighResolution;  
     
    #endregion //Public Fields  
     
    #region Private Fields  
    private long elapsed;          
    private bool isRunning;  
    private long startTimeStamp;  
      
    private static readonly double tickFrequency;  
    #endregion //Private Fields  
    #region Constructors  
    static Stopwatch()  
    {  
        if (!QueryPerformanceFrequency(out Stopwatch.Frequency))  
        {  
            Stopwatch.IsHighResolution = false;  
            Stopwatch.Frequency = TimeSpan.TicksPerSecond;  
            Stopwatch.tickFrequency = 1;  
        }  
        else  
        {  
            Stopwatch.IsHighResolution = true;  
            Stopwatch.tickFrequency = TimeSpan.TicksPerSecond;  
            Stopwatch.tickFrequency /= ((double)Stopwatch.Frequency);  
        }  
    }  
      
    /// <summary>Initializes a new instance of the Stopwatch class.</summary>  
    public Stopwatch()  
    {  
        this.Reset();  
    }  
    #endregion //Constructors  
     
    #region Private Methods  
    private long GetElapsedDateTimeTicks()  
    {  
        long ticks = this.GetRawElapsedTicks();  
        if (Stopwatch.IsHighResolution)  
        {  
            double highTicks = ticks;  
            highTicks *= Stopwatch.tickFrequency;  
            return (long)highTicks;  
        }  
        return ticks;  
    }  
    private long GetRawElapsedTicks()          
    {  
        long elapsedTimestamp = this.elapsed;  
        if (this.isRunning)  
        {  
            long currentTimestamp = Stopwatch.GetTimestamp();  
            long endTimestamp = currentTimestamp - this.startTimeStamp;  
            elapsedTimestamp += endTimestamp;  
        }  
        return elapsedTimestamp;  
    }  
    #endregion //Private Methods  
    #region Public Methods  
    /// <summary>Gets the current number of ticks in the timer mechanism.</summary>  
    /// <returns>A long integer representing the tick counter value of the underlying timer mechanism.</returns>  
    public static long GetTimestamp()          
    {  
        if (Stopwatch.IsHighResolution)  
        {  
            long ticks = 0;  
            QueryPerformanceCounter(out ticks);  
            return ticks;  
        }  
        return DateTime.UtcNow.Ticks;  
    }  
    /// <summary>Stops time interval measurement and resets the elapsed time to zero.</summary>  
    public void Reset()          
    {  
        this.elapsed = 0;  
        this.isRunning = false;  
        this.startTimeStamp = 0;  
    }  
    /// <summary>Starts, or resumes, measuring elapsed time for an interval.</summary>  
    public void Start()          
    {  
        if (!this.isRunning)  
        {  
            this.startTimeStamp = Stopwatch.GetTimestamp();  
            this.isRunning = true;  
        }  
    }  
    /// <summary>Initializes a new Stopwatch instance, sets the elapsed time property to zero, and starts measuring elapsed time.</summary>  
    /// <returns>A Stopwatch that has just begun measuring elapsed time.</returns>  
    public static Stopwatch StartNew()          
    {  
        Stopwatch stopwatch = new Stopwatch();  
        stopwatch.Start();  
        return stopwatch;  
    }  
    /// <summary>Stops measuring elapsed time for an interval.</summary>  
    public void Stop()          
    {  
        if (this.isRunning)  
        {  
            long currentTimestamp = Stopwatch.GetTimestamp();  
            long endTimestamp = currentTimestamp - this.startTimeStamp;  
            this.elapsed += endTimestamp;  
            this.isRunning = false;  
        }  
    }  
    #endregion //Public Methods  
     
    #region Public Properties  
    /// <summary>Gets the total elapsed time measured by the current instance.</summary>  
    /// <value>A read-only System.TimeSpan representing the total elapsed time measured by the current instance.</value>  
    public TimeSpan Elapsed  
    {  
        get { return new TimeSpan(this.GetElapsedDateTimeTicks()); }  
    }  
      
    /// <summary>Gets the total elapsed time measured by the current instance, in milliseconds.</summary>  
    public long ElapsedMilliseconds  
    {  
        get { return (this.GetElapsedDateTimeTicks() / TimeSpan.TicksPerMillisecond); }  
    }  
    /// <summary>Gets the total elapsed time measured by the current instance, in timer ticks.</summary>  
    public long ElapsedTicks  
    {  
        get { return this.GetRawElapsedTicks(); }  
    }  
      
    /// <summary>Gets a value indicating whether the Stopwatch timer is running.</summary>  
    public bool IsRunning  
    {  
        get { return this.isRunning; }  
    }  
    #endregion //Public Properties  
}

public string MakePlural(string name)  
{  
    Regex plural1 = new Regex("(?<keep>[^aeiou])y$");  
    Regex plural2 = new Regex("(?<keep>[aeiou]y)$");  
    Regex plural3 = new Regex("(?<keep>[sxzh])$");  
    Regex plural4 = new Regex("(?<keep>[^sxzhy])$");  
  
    if(plural1.IsMatch(name))  
        return plural1.Replace(name, "${keep}ies");  
    else if(plural2.IsMatch(name))  
        return plural2.Replace(name, "${keep}s");  
    else if(plural3.IsMatch(name))  
        return plural3.Replace(name, "${keep}es");  
    else if(plural4.IsMatch(name))  
        return plural4.Replace(name, "${keep}s");  
  
    return name;  
}  
  
public string MakeSingle(string name)  
{  
    Regex single1 = new Regex("(?<keep>[^aeiou])ies$");  
    Regex single2 = new Regex("(?<keep>[aeiou]y)s$");  
    Regex single3 = new Regex("(?<keep>[sxzh])es$");  
    Regex single4 = new Regex("(?<keep>[^sxzhy])s$");  
  
    if(single1.IsMatch(name))  
        return single1.Replace(name, "${keep}y");  
    else if(single2.IsMatch(name))  
        return single2.Replace(name, "${keep}");  
    else if(single3.IsMatch(name))  
        return single3.Replace(name, "${keep}");  
    else if(single4.IsMatch(name))  
        return single4.Replace(name, "${keep}");  
  
    return name;  
}

using System;  
using System.Runtime.InteropServices;  
using System.Text;  
using System.Windows.Forms;  
  
namespace TextUndoBuffer  
{  
    /// <summary>    
    /// Work around for KB 812943, The RichEdit Control Undo    
    /// Information May Be Lost When the Control Retrieves Text.   
    /// </summary>    
    public class RichTextBoxEx : RichTextBox  
    {  
        // RichEdit messages (Richedit.h)   
        private const int EM_GETTEXTEX = (WM_USER + 94);  
        private const int EM_GETTEXTLENGTHEX = (WM_USER + 95);  
        // Flags for the GETEXTEX data structure   
        private const int GT_DEFAULT = 0;  
        // Flags for the GETTEXTLENGTHEX data structure   
        // Fast computation of a "close" answer   
        private const int GTL_CLOSE = 4;  
        // Do default (return # of chars)   
        private const int GTL_DEFAULT = 0;   
        private const int WM_USER = 0x0400;  
  
        public override string Text  
        {  
            get  
            {  
                GETTEXTLENGTHEX getLength = new GETTEXTLENGTHEX();  
                getLength.flags = GTL_CLOSE; //get buffer size   
                getLength.codepage = 1200; //Unicode   
                  
                int textLength = SendMessage(  
                    base.Handle, EM_GETTEXTLENGTHEX,   
                    ref getLength, 0);  
  
                GETTEXTEX getText = new GETTEXTEX();  
                //add space for null terminator   
                getText.cb = textLength + 2;   
                getText.flags = GT_DEFAULT;  
                getText.codepage = 1200; //Unicode   
                  
                StringBuilder sb = new StringBuilder(getText.cb);  
                  
                SendMessage(base.Handle, EM_GETTEXTEX, ref getText, sb);  
                  
                return sb.ToString();  
            }  
            set  
            {  
                base.Text = value;  
            }  
        }  
  
        public override int TextLength  
        {  
            get  
            {  
                GETTEXTLENGTHEX getLength = new GETTEXTLENGTHEX();  
                //Returns the number of characters   
                getLength.flags = GTL_DEFAULT;   
                getLength.codepage = 1200; //Unicode   
                return SendMessage(base.Handle, EM_GETTEXTLENGTHEX, ref getLength, 0);  
            }  
        }  
  
        [DllImport("user32.dll", EntryPoint = "SendMessage", CharSet = CharSet.Auto)]  
        private static extern int SendMessage(IntPtr hWnd, int msg,  
                                              ref GETTEXTEX wParam, StringBuilder lParam);  
  
        [DllImport("user32.dll", EntryPoint = "SendMessage", CharSet = CharSet.Auto)]  
        private static extern int SendMessage(IntPtr hWnd, int msg,  
                                              ref GETTEXTLENGTHEX wParam, int lParam);  
 
        #region Nested type: GETTEXTEX  
  
        [StructLayout(LayoutKind.Sequential)]  
        private struct GETTEXTEX  
        {  
            public Int32 cb;  
            public Int32 flags;  
            public Int32 codepage;  
            public IntPtr lpDefaultChar;  
            public IntPtr lpUsedDefChar;  
        }  
 
        #endregion  
 
        #region Nested type: GETTEXTLENGTHEX  
  
        [StructLayout(LayoutKind.Sequential)]  
        private struct GETTEXTLENGTHEX  
        {  
            public Int32 flags;  
            public Int32 codepage;  
        }  
 
        #endregion  
    }  
}