计算方法或模块的执行时间

/// <summary>
/// 计算执行时间的类
/// </summary>
public class QueryPerformance
{
    [DllImport("Kernel32.dll")]
    private static extern bool QueryPerformanceCounter(out long performanceCount);

    [DllImport("Kernel32.dll")]
    private static extern bool QueryPerformanceFrequency(out long frequency);

    private long begintTime = 0;//开始时间  

    private long endTime = 0;//结束时间  

    private long frequency = 0;//处理器频率  
    /// <summary>
    /// 开始时间
    /// </summary>
    public long BegintTime
    {
        get { return begintTime; }
    }
    /// <summary>
    /// 结束时间
    /// </summary>
    public long EndTime
    {
        get { return endTime; }
    }
    /// <summary>
    /// CPU频率
    /// </summary>
    public long Frequency
    {
        get { return frequency; }
    }
    /// <summary>
    /// 构造函数，获取CPU频率
    /// </summary>
    public QueryPerformance()
    {
        QueryPerformanceFrequency(out frequency);//获取频率  
    }
    /// <summary>
    /// 开始计算
    /// </summary>
    public void Start()
    {
        QueryPerformanceCounter(out begintTime);
    }
    /// <summary>
    /// 停止计时
    /// </summary>
    /// <param name="showRecord">是否输出计时</param>
    /// <returns>计时</returns>
    public double Stop(bool showRecord)
    {
        QueryPerformanceCounter(out endTime);

        if (showRecord)
        {
            return TastTime;
        }
        return 0.0D;
    }
    /// <summary>
    /// 花费的时间
    /// </summary>
    public double TastTime//花费时间：单位S  
    {
        get
        {
            if (frequency > 0)
                return (double)(endTime - begintTime) / frequency;
            else
                return 0;
        }
    }
}

接下来是使用方法：

QueryPerformance queryPerformance = new QueryPerformance();
queryPerformance.Start();  

//需要知道执行时间的模块

double time = queryPerformance.Stop(true);