C# 监控网速

主要有两个类，其一是NetworkAdapter，该类的作用是获取本机网络适配器列表，并且可以通过该类的属性获取当前网速数据；其二是NetworkMonitor，该类是通过.NET的PerformanceCounter（性能计数器组件）监测本机每一个网络适配器对应的当前网速状况（翻译得不大好，具体还是看原汁原味的代码吧:)）

NetworkAdapter类

using System;
using System.Diagnostics;

namespace NetWorkSpeedMonitor
{
    /// <summary>
    /// Represents a network adapter installed on the machine.
    /// Properties of this class can be used to obtain current network speed.
    /// </summary>
    public class NetworkAdapter
    {
        /// <summary>
        /// Instances of this class are supposed to be created only in an NetworkMonitor.
        /// </summary>
        internal NetworkAdapter(string name)
        {
            this.name = name;
        }

        private long dlSpeed, ulSpeed;         // Download/Upload speed in bytes per second.
        private long dlValue, ulValue;         // Download/Upload counter value in bytes.
        private long dlValueOld, ulValueOld; // Download/Upload counter value one second earlier, in bytes.

        internal string name;                                // The name of the adapter.
        internal PerformanceCounter dlCounter, ulCounter;    // Performance counters to monitor download and upload speed.
        /// <summary>
        /// Preparations for monitoring.
        /// </summary>
        internal void init()
        {
            // Since dlValueOld and ulValueOld are used in method refresh() to calculate network speed, they must have be initialized.
            this.dlValueOld = this.dlCounter.NextSample().RawValue;
            this.ulValueOld = this.ulCounter.NextSample().RawValue;
        }
        /// <summary>
        /// Obtain new sample from performance counters, and refresh the values saved in dlSpeed, ulSpeed, etc.
        /// This method is supposed to be called only in NetworkMonitor, one time every second.
        /// </summary>
        internal void refresh()
        {
            this.dlValue = this.dlCounter.NextSample().RawValue;
            this.ulValue = this.ulCounter.NextSample().RawValue;

            // Calculates download and upload speed.
            this.dlSpeed = this.dlValue - this.dlValueOld;
            this.ulSpeed = this.ulValue - this.ulValueOld;

            this.dlValueOld = this.dlValue;
            this.ulValueOld = this.ulValue;
        }
        /// <summary>
        /// Overrides method to return the name of the adapter.
        /// </summary>
        /// <returns>The name of the adapter.</returns>
        public override string ToString()
        {
            return this.name;
        }
        /// <summary>
        /// The name of the network adapter.
        /// </summary>
        public string Name
        {
            get { return this.name; }
        }
        /// <summary>
        /// Current download speed in bytes per second.
        /// </summary>
        public long DownloadSpeed
        {
            get { return this.dlSpeed; }
        }
        /// <summary>
        /// Current upload speed in bytes per second.
        /// </summary>
        public long UploadSpeed
        {
            get { return this.ulSpeed; }
        }
        /// <summary>
        /// Current download speed in kbytes per second.
        /// </summary>
        public double DownloadSpeedKbps
        {
            get { return this.dlSpeed / 1024.0; }
        }
        /// <summary>
        /// Current upload speed in kbytes per second.
        /// </summary>
        public double UploadSpeedKbps
        {
            get { return this.ulSpeed / 1024.0; }
        }
    }
}

NetworkMonitor类

using System;
using System.Timers;
using System.Collections;
using System.Diagnostics;

namespace NetWorkSpeedMonitor
{
    /// <summary>
    /// The NetworkMonitor class monitors network speed for each network adapter on the computer,
    /// using classes for Performance counter in .NET library.
    /// </summary>
    public class NetworkMonitor
    {
        private Timer timer;                // The timer event executes every second to refresh the values in adapters.
        private ArrayList adapters;            // The list of adapters on the computer.
        private ArrayList monitoredAdapters;// The list of currently monitored adapters.

        public NetworkMonitor()
        {
            this.adapters = new ArrayList();
            this.monitoredAdapters = new ArrayList();
            EnumerateNetworkAdapters();

            timer = new Timer();
            timer.Elapsed += new ElapsedEventHandler(timer_Elapsed);
        }
        /// <summary>
        /// Enumerates network adapters installed on the computer.
        /// </summary>
        private void EnumerateNetworkAdapters()
        {
            PerformanceCounterCategory category = new PerformanceCounterCategory("Network Interface");

            foreach (string name in category.GetInstanceNames())
            {
                // This one exists on every computer.
                if (name == "MS TCP Loopback interface")
                    continue;
                // Create an instance of NetworkAdapter class, and create performance counters for it.
                NetworkAdapter adapter = new NetworkAdapter(name);
                adapter.dlCounter = new PerformanceCounter("Network Interface", "Bytes Received/sec", name);
                adapter.ulCounter = new PerformanceCounter("Network Interface", "Bytes Sent/sec", name);
                this.adapters.Add(adapter);    // Add it to ArrayList adapter
            }
        }

        private void timer_Elapsed(object sender, ElapsedEventArgs e)
        {
            foreach (NetworkAdapter adapter in this.monitoredAdapters)
                adapter.refresh();
        }
        /// <summary>
        /// Get instances of NetworkAdapter for installed adapters on this computer.
        /// </summary>
        public NetworkAdapter[] Adapters
        {
            get { return (NetworkAdapter[])this.adapters.ToArray(typeof(NetworkAdapter)); }
        }
        /// <summary>
        /// Enable the timer and add all adapters to the monitoredAdapters list,
        /// unless the adapters list is empty.
        /// </summary>
        public void StartMonitoring()
        {
            if (this.adapters.Count > )
            {
                foreach (NetworkAdapter adapter in this.adapters)
                    if (!this.monitoredAdapters.Contains(adapter))
                    {
                        this.monitoredAdapters.Add(adapter);
                        adapter.init();
                    }

                timer.Enabled = true;
            }
        }
        /// <summary>
        /// Enable the timer, and add the specified adapter to the monitoredAdapters list
        /// </summary>
        public void StartMonitoring(NetworkAdapter adapter)
        {
            if (!this.monitoredAdapters.Contains(adapter))
            {
                this.monitoredAdapters.Add(adapter);
                adapter.init();
            }
            timer.Enabled = true;
        }
        /// <summary>
        /// Disable the timer, and clear the monitoredAdapters list.
        /// </summary>
        public void StopMonitoring()
        {
            this.monitoredAdapters.Clear();
            timer.Enabled = false;
        }
        /// <summary>
        /// Remove the specified adapter from the monitoredAdapters list, and
        /// disable the timer if the monitoredAdapters list is empty.
        /// </summary>
        public void StopMonitoring(NetworkAdapter adapter)
        {
            if (this.monitoredAdapters.Contains(adapter))
                this.monitoredAdapters.Remove(adapter);
            if (this.monitoredAdapters.Count == )
                timer.Enabled = false;
        }
    }
}

Form关键代码

using NetWorkSpeedMonitor;

        private NetworkAdapter[] adapters;
        private NetworkMonitor monitor;

        private void FormMain_Load(object sender, System.EventArgs e)
        {
            monitor = new NetworkMonitor();
            this.adapters = monitor.Adapters;
            /* If the length of adapters is zero, then no instance
             * exists in the networking category of performance console.*/
            if (adapters.Length == )
            {
                this.ListAdapters.Enabled = false;
                MessageBox.Show("No network adapters found on this computer.");
                return;
            }
            this.ListAdapters.Items.AddRange(this.adapters);
        }

        private void ListAdapters_SelectedIndexChanged(object sender, System.EventArgs e)
        {
            monitor.StopMonitoring();
            // Start a timer to obtain new performance counter sample every second.
            monitor.StartMonitoring(adapters[this.ListAdapters.SelectedIndex]);
            this.TimerCounter.Start();
        }

        private void TimerCounter_Tick(object sender, System.EventArgs e)
        {
            NetworkAdapter adapter = this.adapters[this.ListAdapters.SelectedIndex];
            /* The DownloadSpeedKbps and UploadSpeedKbps are double values. You can also
             * use properties DownloadSpeed and UploadSpeed, which are long values but
             * are measured in bytes per second. */
            this.LableDownloadValue.Text = String.Format("{0:n} kbps", adapter.DownloadSpeedKbps);
            this.LabelUploadValue.Text = String.Format("{0:n} kbps", adapter.UploadSpeedKbps);
        }