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PingCompletedEventHandler Delegate

Definition

Represents the method that will handle the PingCompleted event of a Ping object.

public delegate void PingCompletedEventHandler(System::Object ^ sender, PingCompletedEventArgs ^ e);
public delegate void PingCompletedEventHandler(object sender, PingCompletedEventArgs e);
type PingCompletedEventHandler = delegate of obj * PingCompletedEventArgs -> unit
Public Delegate Sub PingCompletedEventHandler(sender As Object, e As PingCompletedEventArgs)

Parameters

sender
Object

The source of the PingCompleted event.

e
PingCompletedEventArgs

A PingCompletedEventArgs object that contains the event data.

Examples

The following code example demonstrates specifying a PingCompletedEventHandler to respond to a PingCompleted event.

#using <System.dll>

using namespace System;
using namespace System::Text;
using namespace System::Net;
using namespace System::Net::NetworkInformation;
using namespace System::ComponentModel;
using namespace System::Threading;
void PingCompletedCallback( Object^ sender, PingCompletedEventArgs^ e );
void DisplayReply( PingReply^ reply );
int main()
{
   array<String^>^args = Environment::GetCommandLineArgs();
   if ( args->Length == 1 )
      throw gcnew ArgumentException( "Ping needs a host or IP Address." );

   String^ who = args[ 1 ];
   AutoResetEvent^ waiter = gcnew AutoResetEvent( false );
   
   Ping ^ pingSender = gcnew Ping;
   
   // When the PingCompleted event is raised,
   // the PingCompletedCallback method is called.
   pingSender->PingCompleted += gcnew PingCompletedEventHandler( PingCompletedCallback );
   
   // Create a buffer of 32 bytes of data to be transmitted.
   String^ data = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
   array<Byte>^buffer = Encoding::ASCII->GetBytes( data );
   
   // Wait 12 seconds for a reply.
   int timeout = 12000;
   
   // Set options for transmission:
   // The data can go through 64 gateways or routers
   // before it is destroyed, and the data packet
   // cannot be fragmented.
   PingOptions ^ options = gcnew PingOptions( 64,true );
   Console::WriteLine( "Time to live: {0}", options->Ttl );
   Console::WriteLine( "Don't fragment: {0}", options->DontFragment );
   
   // Send the ping asynchronously.
   // Use the waiter as the user token.
   // When the callback completes, it can wake up this thread.
   pingSender->SendAsync( who, timeout, buffer, options, waiter );
   
   // Prevent this example application from ending.
   // A real application should do something useful
   // when possible.
   waiter->WaitOne();
   Console::WriteLine( "Ping example completed." );
}


void PingCompletedCallback( Object^ /*sender*/, PingCompletedEventArgs^ e )
{
   
   // If the operation was canceled, display a message to the user.
   if ( e->Cancelled )
   {
      Console::WriteLine( "Ping canceled." );
      
      // Let the main thread resume. 
      // UserToken is the AutoResetEvent object that the main thread 
      // is waiting for.
      (dynamic_cast<AutoResetEvent^>(e->UserState))->Set();
   }

   
   // If an error occurred, display the exception to the user.
   if ( e->Error != nullptr )
   {
      Console::WriteLine( "Ping failed:" );
      Console::WriteLine( e->Error->ToString() );
      
      // Let the main thread resume. 
      (dynamic_cast<AutoResetEvent^>(e->UserState))->Set();
   }

   PingReply ^ reply = e->Reply;
   DisplayReply( reply );
   
   // Let the main thread resume.
   (dynamic_cast<AutoResetEvent^>(e->UserState))->Set();
}


void DisplayReply( PingReply ^ reply )
{
   if ( reply == nullptr )
      return;

   Console::WriteLine( "ping status: {0}", reply->Status );
   if ( reply->Status == IPStatus::Success )
   {
      Console::WriteLine( "Address: {0}", reply->Address->ToString() );
      Console::WriteLine( "RoundTrip time: {0}", reply->RoundtripTime );
      Console::WriteLine( "Time to live: {0}", reply->Options->Ttl );
      Console::WriteLine( "Don't fragment: {0}", reply->Options->DontFragment );
      Console::WriteLine( "Buffer size: {0}", reply->Buffer->Length );
   }
}
using System;
using System.Text;
using System.Net;
using System.Net.NetworkInformation;
using System.ComponentModel;
using System.Threading;

namespace Examples.System.Net.NetworkInformation.PingTest
{
    public class PingExample
    {
        public static void Main (string[] args)
        {
            if (args.Length == 0)
                throw new ArgumentException ("Ping needs a host or IP Address.");

            string who = args[0];
            AutoResetEvent waiter = new AutoResetEvent (false);

            Ping pingSender = new Ping ();

            // When the PingCompleted event is raised,
            // the PingCompletedCallback method is called.
            pingSender.PingCompleted += new PingCompletedEventHandler (PingCompletedCallback);

            // Create a buffer of 32 bytes of data to be transmitted.
            string data = "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa";
            byte[] buffer = Encoding.ASCII.GetBytes (data);

            // Wait 12 seconds for a reply.
            int timeout = 12000;

            // Set options for transmission:
            // The data can go through 64 gateways or routers
            // before it is destroyed, and the data packet
            // cannot be fragmented.
            PingOptions options = new PingOptions (64, true);

            Console.WriteLine ("Time to live: {0}", options.Ttl);
            Console.WriteLine ("Don't fragment: {0}", options.DontFragment);

            // Send the ping asynchronously.
            // Use the waiter as the user token.
            // When the callback completes, it can wake up this thread.
            pingSender.SendAsync(who, timeout, buffer, options, waiter);

            // Prevent this example application from ending.
            // A real application should do something useful
            // when possible.
            waiter.WaitOne ();
            Console.WriteLine ("Ping example completed.");
        }

        private static void PingCompletedCallback (object sender, PingCompletedEventArgs e)
        {
            // If the operation was canceled, display a message to the user.
            if (e.Cancelled)
            {
                Console.WriteLine ("Ping canceled.");

                // Let the main thread resume.
                // UserToken is the AutoResetEvent object that the main thread
                // is waiting for.
                ((AutoResetEvent)e.UserState).Set ();
            }

            // If an error occurred, display the exception to the user.
            if (e.Error != null)
            {
                Console.WriteLine ("Ping failed:");
                Console.WriteLine (e.Error.ToString ());

                // Let the main thread resume.
                ((AutoResetEvent)e.UserState).Set();
            }

            PingReply reply = e.Reply;

            DisplayReply (reply);

            // Let the main thread resume.
            ((AutoResetEvent)e.UserState).Set();
        }

        public static void DisplayReply (PingReply reply)
        {
            if (reply == null)
                return;

            Console.WriteLine ("ping status: {0}", reply.Status);
            if (reply.Status == IPStatus.Success)
            {
                Console.WriteLine ("Address: {0}", reply.Address.ToString ());
                Console.WriteLine ("RoundTrip time: {0}", reply.RoundtripTime);
                Console.WriteLine ("Time to live: {0}", reply.Options.Ttl);
                Console.WriteLine ("Don't fragment: {0}", reply.Options.DontFragment);
                Console.WriteLine ("Buffer size: {0}", reply.Buffer.Length);
            }
        }
    }
}

Remarks

User data that is specified in a SendAsync call is available to the method invoked by this delegate in the UserState property.

Extension Methods

GetMethodInfo(Delegate)

Gets an object that represents the method represented by the specified delegate.

Applies to