Below is a sample class containing a high performance timer. Example usuage:
PerformanceTimer pf = new PerformanceTimer(true);
float timeMs = pf.GetTimeMs();using System;
using System.Runtime.InteropServices;
///
/// This class can be used to gather accurate performance timings.
///
public class PerformanceTimer
{
[DllImport("kernel32.dll")]
internal static extern bool QueryPerformanceCounter(ref long lpPerformanceCount);
[DllImport("kernel32.dll")]
internal static extern bool QueryPerformanceFrequency(ref long lpFrequency);
#region Private Variables
private bool _isRunning = false;
private long _startTime = 0;
private long _frequency = 0;
private float _elapsed = 0;
#endregion Private Variables
#region Constructors
///
/// Default constructor - does not start timer immediately.
///
public PerformanceTimer()
{
}
///
/// Constructor with option to start timer at same time.
///
///Whether to start timer immediately.
public PerformanceTimer(bool startTimer)
{
if (startTimer)
{
Start();
}
}
#endregion Constructors
#region Public Properties
///
/// Returns True if the timer is currently running.
///
/// To change the running state use the Start and Stop methods provided.
public bool IsRunning
{
get { return _isRunning; }
}
#endregion Public Properties
#region Public Methods
///
/// Starts the performance timer running.
///
public void Start()
{
QueryPerformanceFrequency(ref _frequency);
QueryPerformanceCounter(ref _startTime);
_elapsed = 0;
_isRunning = true;
}
///
/// Stops the performance timer running.
///
public void Stop()
{
// Call procedure that will set internal elapsed variable, then turn running flag off.
GetTime();
_isRunning = false;
}
///
/// Returns the time elapsed since "Start" was called (in seconds). If the timer
/// is not running the time elapsed between the last start and stop time is returned.
///
/// A float representing the time ellapsed (in seconds)
public float GetTime()
{
if (_isRunning)
{
long endTime = 0;
QueryPerformanceCounter(ref endTime);
_elapsed = (float)(endTime - _startTime) / _frequency;
return _elapsed;
}
else
{
return _elapsed;
}
}
///
/// Returns the time elapsed since "Start" was called (in milliseconds). If the timer
/// is not running the time elapsed between the last start and stop time is returned.
///
/// A float representing the time ellapsed (in milliseconds)
public float GetTimeMs()
{
if (_isRunning)
{
return GetTime() * 1000;
}
else
{
return _elapsed * 1000;
}
}
///
/// Override ToString to display time nicely formatted.
///
/// Returns the time formatted as a string.
public override string ToString()
{
return String.Format("{0:0000.000}s ", GetTime());
}
#endregion Public Methods}