用C#实时获取CPU利用率

using  System;
using  System.Collections.Generic;
using  System.Text;
using  System.Runtime.InteropServices;
using  System.Threading;
using  System.Diagnostics; 

namespace  ConsoleApplication2
... {
    public delegate bool CallBack(int hwnd, int lParam);

    class EnumWindowsApp
    ...{

        [DllImport("user32")]

        public static extern int EnumWindows(CallBack x, int y);

        private const string CategoryName = "Processor";
        private const string CounterName = "% Processor Time";
        private const string InstanceName = "_Total";
        private static void Say(string txt)
        ...{
            Console.WriteLine(txt);
        }

        //  auxiliary  print  methods  
        private static void Say()
        ...{
            Say("");
        }

        static void Main(string[] args)
        ...{
            try
            ...{
                //CallBack myCallBack = new CallBack(EnumWindowsApp.Report);

                //EnumWindows(myCallBack, 0);
                //Console.Read();
                Say("$Id:  CpuLoadInfo.cs,v  1.2  2007/07/03  17:45:48  rz65  Exp  $");
                Say();

                Say("Attempt  to  create  a  PerformanceCounter  instance:");
                Say("Category  name  =  " + CategoryName);
                Say("Counter  name    =  " + CounterName);
                Say("Instance  name  =  " + InstanceName);
                PerformanceCounter pc = new PerformanceCounter(CategoryName, CounterName, InstanceName);
                Say("Performance  counter  was  created.");
                Say("Property  CounterType:  " + pc.CounterType);
                Say();

                Say("Property  CounterHelp:  " + pc.CounterHelp);
                Say();
                Say("Entering  measurement  loop.");

                while (true)
                ...{
                    Thread.Sleep(1000);  //  wait  for  1  second
                    float cpuLoad = pc.NextValue();//.Nextvalue();
                    Say("CPU  load  =  " + cpuLoad + "  %.");
                }
            }
            catch(InvalidOperationException er)

            ...{
                Console.WriteLine(er);
                Console.Read();
            }
        }
        public static bool Report(int hwnd, int lParam)
        ...{

            Console.Write("Window handle is :");

            Console.WriteLine(hwnd);

            return true;

        } 

    }
}