如何计算网络速度？

Question

已解决：

我正在使用WCF通过流式传输文件。客户端在服务中调用方法，然后服务从客户端获取文件。在途中，我通过CallBack发回速度。

我的问题是，我无法确定我计算的是哪种速度。当服务从客户端获取文件时，它使用下载速度。但是，当客户端发送文件时，它是上传速度。我需要计算哪一个，以及如何计算？

没有解决尚未：

当客户端调用服务的方法（和用参考文件给它的流），它需要TOO长（取决于的大小文件）从客户端调用方法开始直到服务的方法开始激活。为什么会发生？一个千兆字节的文件将永远占用。

*从服务的方法开始的时候，所有的东西都可以正常工作，没有问题。因此，展示服务是浪费时间。

（客户端）

Stream TheStream = File.OpenRead(@"C:\BigFile.rar"); 
Service1.GiveAFile(TheStream); 

感谢。

Answer 1

来源：How to calculate network bandwidth speed in c#

CODE: 
using System; 
using System.Net.NetworkInformation; 
using System.Windows.Forms; 

namespace InterfaceTrafficWatch 
{ 
    /// <summary> 
    /// Network Interface Traffic Watch 
    /// by Mohamed Mansour 
    /// 
    /// Free to use under GPL open source license! 
    /// </summary> 
    public partial class MainForm : Form 
    { 
     /// <summary> 
     /// Timer Update (every 1 sec) 
     /// </summary> 
     private const double timerUpdate = 1000; 

     /// <summary> 
     /// Interface Storage 
     /// </summary> 
     private NetworkInterface[] nicArr; 

     /// <summary> 
     /// Main Timer Object 
     /// (we could use something more efficient such 
     /// as interop calls to HighPerformanceTimers) 
     /// </summary> 
     private Timer timer; 

     /// <summary> 
     /// Constructor 
     /// </summary> 
     public MainForm() 
     { 
      InitializeComponent(); 
      InitializeNetworkInterface(); 
      InitializeTimer(); 
     } 

     /// <summary> 
     /// Initialize all network interfaces on this computer 
     /// </summary> 
     private void InitializeNetworkInterface() 
     { 
      // Grab all local interfaces to this computer 
      nicArr = NetworkInterface.GetAllNetworkInterfaces(); 

      // Add each interface name to the combo box 
      for (int i = 0; i < nicArr.Length; i++) 
       cmbInterface.Items.Add(nicArr[i].Name); 

      // Change the initial selection to the first interface 
      cmbInterface.SelectedIndex = 0; 
     } 

     /// <summary> 
     /// Initialize the Timer 
     /// </summary> 
     private void InitializeTimer() 
     { 
      timer = new Timer(); 
      timer.Interval = (int)timerUpdate; 
      timer.Tick += new EventHandler(timer_Tick); 
      timer.Start(); 
     } 

     /// <summary> 
     /// Update GUI components for the network interfaces 
     /// </summary> 
     private void UpdateNetworkInterface() 
     { 
      // Grab NetworkInterface object that describes the current interface 
      NetworkInterface nic = nicArr[cmbInterface.SelectedIndex]; 

      // Grab the stats for that interface 
      IPv4InterfaceStatistics interfaceStats = nic.GetIPv4Statistics(); 

      // Calculate the speed of bytes going in and out 
      // NOTE: we could use something faster and more reliable than Windows Forms Tiemr 
      //  such as HighPerformanceTimer http://www.m0interactive.com/archives/2006/12/21/high_resolution_timer_in_net_2_0.html 
      int bytesSentSpeed = (int)(interfaceStats.BytesSent - double.Parse(lblBytesSent.Text))/1024; 
      int bytesReceivedSpeed = (int)(interfaceStats.BytesReceived - double.Parse(lblBytesReceived.Text))/1024; 

      // Update the labels 
      lblSpeed.Text = nic.Speed.ToString(); 
      lblInterfaceType.Text = nic.NetworkInterfaceType.ToString(); 
      lblSpeed.Text = nic.Speed.ToString(); 
      lblBytesReceived.Text = interfaceStats.BytesReceived.ToString(); 
      lblBytesSent.Text = interfaceStats.BytesSent.ToString(); 
      lblUpload.Text = bytesSentSpeed.ToString() + " KB/s"; 
      lblDownload.Text = bytesReceivedSpeed.ToString() + " KB/s"; 

     } 

     /// <summary> 
     /// The Timer event for each Tick (second) to update the UI 
     /// </summary> 
     /// <param name="sender"></param> 
     /// <param name="e"></param> 
     void timer_Tick(object sender, EventArgs e) 
     { 
      UpdateNetworkInterface(); 
     } 

    } 
} 

Answer 2

对于第二个问题：

最有可能您的服务加载整个文件到内存流回客户端之前。

你可以看看下面的问题，以了解如何正确分块。

How can I read/stream a file without loading the entire file into memory?