ComponentPro UltimateFtp

      KeepAliveAsync(AsyncCompletedEventHandler, Object) Method

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      Begins an asynchronous operation to send a command or data packet to the server to keep the connection alive.

      Syntax

      public Task KeepAliveAsync(
         AsyncCompletedEventHandler callback, 
         object userState = null
      )

      Parameters

      callback
      An optional asynchronous callback to be invoked when this operation completes. This parameter can be null.
      userState
      A user-provided object that identifies this particular asynchronous operation.

      Return Value

      An object that references the asynchronous operation.

      Examples

      Shows how to use KeepAliveAsync method to keep the connection alive (Task-based approach).

      using System;
      using System.ComponentModel;
      using ComponentPro.IO;
      using ComponentPro.Net;
      using ComponentPro;
      
      ...
      
      async static void Main1()
      {
          // Create a new class instance. 
          Ftp client = new Ftp();
      
          // Connect to the FTP server. 
          client.Connect("myserver");
      
          // Authenticate. 
          client.Authenticate("userName", "password");
      
          // ... 
       
          // Keep the connection alive. 
          await client.KeepAliveAsync(callback1, "user state");
      
          // ... 
       
          // Disconnect. 
          client.Disconnect();
      }
      
      private static void callback1(object sender, AsyncCompletedEventArgs e)
      {
          if (e.Error != null)
              Console.WriteLine("Error: " + e.Error.ToString());
      
          Console.WriteLine("Method completed. User state: " + e.UserState);
      }

      Shows how to use the KeepAliveAsync method to keep the connection alive (Event-based approach).

      using System;
      using System.ComponentModel;
      using ComponentPro.IO;
      using ComponentPro.Net;
      using ComponentPro;
      
      ...
      
      static void Main1()
      {
          // Create a new class instance. 
          Ftp client = new Ftp();
      
          // Connect to the FTP server. 
          client.Connect("myserver");
      
          // Authenticate. 
          client.Authenticate("userName", "password");
      
          // ... 
       
          // Send NOOP command to the server. 
          client.KeepAliveAsync(callback1, "user state");
      
          // ... 
       
          // Disconnect. 
          client.Disconnect();
      }
      
      static void callback1(object sender, AsyncCompletedEventArgs e)
      {
          // Ftp client = (Ftp)sender; 
          if (e.Error != null)
              Console.WriteLine("Error: " + e.Error.Message);
      
          Console.WriteLine("Method completed. User-state: " + e.UserState);
      }

      Framework

      .NET Compact Framework.NET Compact Framework

      Supported version: 2.0, 3.5, and 3.9
      Assembly: ComponentPro.Ftp.CF (in ComponentPro.Ftp.CF.dll)

      .NET Framework.NET Framework

      Supported version: 2.0, 3.0, 3.5, 4.0, 4.5.x, 4.6.x and later
      Assembly: ComponentPro.Ftp (in ComponentPro.Ftp.dll)

      Portable Class Library for Windows Phone 8.1 and Windows 8.1 Store AppsPortable Class Library for Windows Phone 8.1 and Windows 8.1 Store Apps

      Supported version: 4.6.x and later
      Assembly: ComponentPro.Ftp.WinPcl (in ComponentPro.Ftp.WinPcl.dll)

      Universal Windows Platform (includes Windows 10 Mobile, Windows 10 Store Apps and Windows 10 IoT)Universal Windows Platform (includes Windows 10 Mobile, Windows 10 Store Apps and Windows 10 IoT)

      Supported version: 4.6.x and later
      Assembly: ComponentPro.Ftp.Uwp (in ComponentPro.Ftp.Uwp.dll)

      Xamarin AndroidXamarin Android

      Supported version: 2.3 and later
      Assembly: ComponentPro.Ftp.Android (in ComponentPro.Ftp.Android.dll)

      Xamarin MacXamarin Mac

      Supported version: 2.0.x and later
      Assembly: ComponentPro.Ftp.Mac (in ComponentPro.Ftp.Mac.dll)

      Xamarin iOSXamarin iOS

      Supported version: 5.1.x and later
      Assembly: ComponentPro.Ftp.iOS (in ComponentPro.Ftp.iOS.dll)

      See Also