www.pudn.com > dotnetupdater.rar > ServerPoller.cs

 using System; 
using System.Threading; 
using System.Windows.Forms; 
using System.Reflection; 
using System.IO; 
using System.Diagnostics; 
using System.ComponentModel; 
 
namespace Microsoft.Samples.AppUpdater 
{ 
	/// 
 
	/// Summary description for ServerPoller. 
	/// 
 
	public class ServerPoller 
	{ 
		 
		private AppUpdater AppMan; 
		private Thread PollerThread; 
 
		//************************************************************** 
		// InitalPollInterval Property	 
		// - Seconds between the first check for new updates 
		//************************************************************** 
		private int _InitialPollDelay=15; 
		[DefaultValue(15)] 
		[Description("Seconds between the first check for new updates.")] 
		public int InitialPollInterval 
		{ 
			get { return _InitialPollDelay; } 
			set { _InitialPollDelay = value; } 
		} 
 
		//************************************************************** 
		// PollInterval Property	 
		// - Seconds between the first check for new updates 
		//************************************************************** 
		private int _PollInterval=30; 
		[DefaultValue(30)] 
		[Description("Seconds between each subsequent check for updates.")] 
		public int PollInterval 
		{ 
			get { return _PollInterval; } 
			set { _PollInterval = value; } 
		} 
 
		//************************************************************** 
		// AutoStart Property	 
		// - If true, automatically starts checking for updates on  
		//   AppUpdater Initialize() 
		//************************************************************** 
		private bool _AutoStart=true; 
		[DefaultValue(true)] 
		[Description("Whether or not to automatically start the poll for for updates on startup.")] 
		public bool AutoStart 
		{ 
			get { return _AutoStart; } 
			set { _AutoStart = value; } 
		} 
 
		//************************************************************** 
		// DownloadOnDetection Property	 
		// - If true, automatically starts the download when an update is detected 
		//************************************************************** 
		private bool _DownloadOnDetection=true; 
		[DefaultValue(true)] 
		[Description("Whether or not to automatically start downloading the update when detected.")] 
		public bool DownloadOnDetection 
		{ 
			get { return _DownloadOnDetection; } 
			set { _DownloadOnDetection = value; } 
		} 
 
		//************************************************************** 
		// Constructor()	 
		//************************************************************** 
		public ServerPoller(AppUpdater appMan) 
		{ 
			AppMan = appMan; 
		} 
 
		//************************************************************** 
		// Start()	 
		// - Starts checking for updates 
		//************************************************************** 
		public void Start() 
		{ 
			if (PollerThread == null)  
				PollerThread = new Thread(new ThreadStart(RunThread)); 
			else if (!PollerThread.IsAlive) 
				PollerThread = new Thread(new ThreadStart(RunThread)); 
 
			if (!PollerThread.IsAlive) 
				PollerThread.Start(); 
		} 
 
		//************************************************************** 
		// Stop()	 
		// - Kills the poller thread and stops checking for updates 
		//************************************************************** 
		public void Stop() 
		{ 
			if ((PollerThread != null) && (PollerThread.IsAlive))  
			{ 
				PollerThread.Abort(); 
				PollerThread = null; 
			} 
		} 
 
		//************************************************************** 
		// RunThread()	 
		//************************************************************** 
		public void RunThread() 
		{ 
			int PollRate = InitialPollInterval; 
 
			try { 
				while (true) { 
					Thread.Sleep(TimeSpan.FromSeconds(PollRate)); 
					PollRate = PollInterval; 
 
					bool UpdatesAvailable = false; 
					try  
					{ 
						if (AppMan.Manifest.State.Phase == UpdatePhases.Complete) 
							UpdatesAvailable = AppMan.CheckForUpdates(); 
						else 
							UpdatesAvailable = false; 
					}  
					catch (Exception e)  
					{ 
						//For whatever reason (perhaps the client is disconnected),  
						//we couldn't access the app on the server to check if an updated app  
						//version is available.  In this case, we want to do nothing 
						//& check to see if we can reach the app later 
						Debug.WriteLine(e.ToString()); 
						UpdatesAvailable = false; 
					} 
					if (UpdatesAvailable)  
					{ 
						Debug.WriteLine("APPMANAGER:  New update detected."); 
						 
						//Download & apply the update 
						if (DownloadOnDetection) 
							AppMan.Downloader.Start(); 
						 
						//The updater runs on it's own thread, so stop the poller thread. 
						Stop(); 
					}  
					else  
					{ 
						Debug.WriteLine("APPMANAGER:  New update NOT detected."); 
					} 
				} 
			} 
			catch(Exception) { 
				Debug.WriteLine("APPMANAGER:  The Server Polling thread has stopped."); 
			} 
		} 
	} 
}