Automatic retry for the System.Net.Http.HttpClient - c#

I know Entity Framework has a 'Connection Resiliency and Retry Logic' mechanism to work with unreliable networks.
Is there also such a thing for the System.Net.Http.HttpClient?
So a sort of an automatic retry mechanism so when the connections gets lost or a timeout occurs, then it will retry for x times.
Is that possible?

As far as I know, there is no such mechanism. But you can write yourself an event, checking the connectivity all x milliseconds.
like
public class CheckInternet
{
public CheckInternet()
{
Timer t1 = new Timer();
t1.Interval = 1000;
t1.Tick += T1_Tick;
t1.Start();
}
private void T1_Tick(object sender, EventArgs e)
{
var ping = new System.Net.NetworkInformation.Ping();
var result = ping.Send("www.google.com");
if (result.Status != System.Net.NetworkInformation.IPStatus.Success)
{
// Your code to reconnect here
}
}
public event EventHandler CheckConnectivity;
private void OnCheckConnectivity()
{
CheckConnectivity?.Invoke(this, new EventArgs());
}
}
Now just implement this to your other class use
CheckInternet cki = new CheckInternet();
cki.CheckConnectivity += new cki_CheckConnectivity;

Related

Background worker stealing main thread

So I can't say for sure this is the issue but I'm just about positive it is. I have a recordset of IVR calls to make. I put the data for each one in a concurrent queue and start 5 background workers to start working from the queue. However, after making 2 calls, the calls stop coming until one person hangs up, then it moves on to call number 3,4,5 etc. Are the any issues with this code?
It seems like the background workers are blocking eachother from calling the same method...? Is that possible?
private ConcurrentQueue<DataTable> _ivrCallsQueue = new ConcurrentQueue<DataTable>();
private List<BackgroundWorker> _ivrCallers = new List<BackgroundWorker>();
public overrid void Process()
{
foreach(DataRow row in _tblRecordsToProcess.Rows)
{
_workingActionItem = actionItemDAL.GetActionItemFromId(Convert.ToInt32(row["FNActionItemId"].ToString()));
var workingActionItemsTable = actionItemDAL.GetActionItemParamValues(Convert.ToInt32(row["FNActionItemId"].ToString()));
ivrCallsQueue.Enqueue(workingActionItemsTable);
}
StartCalls();
while (_ivrCallers.Count != 0)
{
testurls = testurls;
}
}
private void StartCalls()
{
int maxLines = 5;
if (_ivrCallsQueue.Count < maxLines)
{
maxLines = _ivrCallsQueue.Count;
}
for (int i = 0; i < maxLines; i++)
{
DataTable workingCall = new DataTable();
_ivrCallsQueue.TryDequeue(out workingCall);
BackgroundWorker ivrCaller = new BackgroundWorker();
_ivrCallers.Add(ivrCaller);
ivrCaller.DoWork += delegate(object sender, DoWorkEventArgs e)
{
RequestIVR(workingCall, Convert.ToInt32(workingCall.Rows[2][0].ToString()));
_ivrCallers.Remove(ivrCaller);
};
ivrCaller.RunWorkerCompleted += (bw_AnalyzeResults);
ivrCaller.RunWorkerAsync();
}
}
private void bw_AnalyzeResults(object sender, RunWorkerCompletedEventArgs e)
{
DataTable workingCall = new DataTable();
if (_ivrCallsQueue.Count != 0)
{
_ivrCallsQueue.TryDequeue(out workingCall);
BackgroundWorker ivrCaller = new BackgroundWorker();
ivrCaller.DoWork += delegate(object completeSender, DoWorkEventArgs completeArgs)
{
RequestIVR(workingCall, Convert.ToInt32(workingCall.Rows[2][0].ToString()));
_ivrCallers.Remove(ivrCaller);
};
ivrCaller.RunWorkerCompleted += (bw_AnalyzeResults);
ivrCaller.RunWorkerAsync();
}
else
{
}
}
private void RequestIVR(DataTable workingTable,int fnActionItemID)
{
var urlRequest = "http://uccx_http_trigger:9080/test?strTestMode=1&strTaskID=" + fnActionItemID;
var webClient = new WebClient { UseDefaultCredentials = true, Proxy = WebRequest.DefaultWebProxy };
DecodeResponseType(GetValueFromElement("Response Code was ", webClient.DownloadString(urlRequest)));
}
This will spawn at most five threads that each attempt to pull the next item from the queue and process it. If the queue is empty the attempt will fail and the thread will simply exit:
private List<System.Threading.Thread> Threads = new List<System.Threading.Thread>();
private ConcurrentQueue<DataTable> _ivrCallsQueue = new ConcurrentQueue<DataTable>();
private void StartCalls()
{
int maxLines = Math.Min(5 , _ivrCallsQueue.Count);
for (int i = 0; i < maxLines; i++ )
{
System.Threading.Thread T = new System.Threading.Thread(delegate()
{
DataTable workingCall;
while (_ivrCallsQueue.TryDequeue(out workingCall))
{
RequestIVR(workingCall, Convert.ToInt32(workingCall.Rows[2][0].ToString()));
}
});
Threads.Add(T);
T.Start();
}
}
The threads will keep running until all the items have been processed.
It looks like bw_AnalyzeResults does pretty much the same thing that StartCalls() does. In other words, when the background worker has finished its work, you immediately enqueue the same work to happen again, recursively forever?
By the looks of it, you want bw_AnalyzeResults to analyze the results returned by calling your web service. That is not what is happening at the moment.
The code below taken from the bw_AnalyzeResults event handler is scheduling a background job and making itself handle the RunWorkerCompleted event. So, presumably the software keeps going around and around executing bw_AnalyzeResults forever until you kill the process?
private void bw_AnalyzeResults(object sender, RunWorkerCompletedEventArgs e)
{
ivrCaller.DoWork += delegate(object completeSender, DoWorkEventArgs completeArgs)
{
RequestIVR(workingCall, Convert.ToInt32(workingCall.Rows[2][0].ToString()));
_ivrCallers.Remove(ivrCaller);
};
ivrCaller.RunWorkerCompleted += (bw_AnalyzeResults);
}

Dispatcher timer is firing twice :(

i have problems with this timer, my function in the Tick event are appearing twice.. i want it to appear only once..
public void timerStart()
{
DispatcherTimer updaterTimer = new DispatcherTimer();
updaterTimer.Tick += new EventHandler(updaterTimer_Tick);
updaterTimer.Interval = new TimeSpan(0,0,0,0,300);
updaterTimer.Start();
}
private void updaterTimer_Tick(object sender, EventArgs e)
{
updaterTimer.Stop();
checkSigningAvailable();
updaterTimer.Start();
}
This is the method that is checked every tick of the timer,
public void checkSigningAvailable()
{
if (dt_signing_in.CompareTo(DateTime.Now) < 0)
{
if (!InPopAlready)
{
InPopAlready = true;
disableSigningIn("False", this.event_id);
}
}
}
And the messagebox in the bottom is appearing twice after calling this function above
public void disableSigningIn(string Out,string event_id)
{
System.Console.WriteLine("POPED "+ InPopAlready);
connection.Open();
string sign = "True," + Out;
string query = "update data_storage set data_details = '" + sign + "' where data_name = 'Signing';";
NpgsqlCommand command = new NpgsqlCommand(query, connection);
command.ExecuteNonQuery();
connection.Close();
sign_in.Content = "Sign-in Time : Over";
string query2 = concatQuery(getIDnumberAttendance(event_id));
updateAbsences(query2);
MessageBox.Show("Signing in is over!", "No more signing in!", MessageBoxButton.OK, MessageBoxImage.Information);
}
You are adding " += new EventHandler " and adding and adding new EventHandlers all over new EventHandlers but never remove them..
All the previous one gets fired each Time the Timer Starts again.
You can reproduce this behaviour if you implement a counter, then you will see that is doubles with each new added and raised Event.
(Edit: Just was confused because the "new" keyword, but actually I will not delete the answer since I am pretty sure that in some cases it will exactly be the issue)
The following may help:
How to remove all event handlers from an event
And here the most easy solution:
(You may polish it by using delegates)
Declaration in Class:
private System.Windows.Threading.DispatcherTimer P5DispatcherHelpsystemTimer = new System.Windows.Threading.DispatcherTimer();
private EventHandler P5DispatcherTimerHandler;
Dispatcher Timer Method:
private void InitializeHelpsystemCronjobs(System.Windows.Controls.Canvas sub_CanvasElement)
{
P5DispatcherTimerHandler = (sender, e) => P5DispatcherHelpsystemTimerTick(sender, e, sub_CanvasElement);
P5DispatcherHelpsystemTimer.Tick += P5DispatcherTimerHandler;
P5DispatcherHelpsystemTimer.Interval = new TimeSpan(0, 0, 1);
P5DispatcherHelpsystemTimer.Start();
}
Dispatcher TimerTick Method:
private void P5DispatcherHelpsystemTimerTick(object sender, EventArgs e, System.Windows.Controls.Canvas sub_CanvasElement)
{
P5DispatcherHelpsystemTimer.Stop();
{
// Do stuff
}
P5DispatcherHelpsystemTimer.Start();
}
// Somewhere when an Trigger Event or Action etc. happens and the Timer shall start:
InitializeHelpsystemCronjobs(HelpsystemHelpCanvas);
// Somewhere when it sahll stop:
P5DispatcherHelpsystemTimer.Stop();
P5DispatcherHelpsystemTimer.Tick -= P5DispatcherTimerHandler;
(If you have more complex situation you definitely need delegate List<>)
For me, it was not starting, stopping or the Timer at all. It was the DI/IOC container resolving two instances of the ViewModel which started a new refresh timer in the constructor. Check to make sure that you are always seeing the same ViewModel instance and not actually two separate ones, firing two separate Timers.
The code below fires the MessageBox only once:
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
this.timerStart();
}
DispatcherTimer updaterTimer;
private bool InPopAlready;
DateTime dt_signing_in;
public void timerStart()
{
updaterTimer = new DispatcherTimer();
updaterTimer.Tick += new EventHandler(updaterTimer_Tick);
updaterTimer.Interval = new TimeSpan(0, 0, 0, 0, 300);
updaterTimer.Start();
}
private void updaterTimer_Tick(object sender, EventArgs e)
{
updaterTimer.Stop();
checkSigningAvailable();
updaterTimer.Start();
}
public void checkSigningAvailable()
{
if (dt_signing_in.CompareTo(DateTime.Now) < 0)
{
if (!InPopAlready)
{
InPopAlready = true;
// Calling your method and showing MessageBox
MessageBox.Show("Signing in is over!", "No more signing in!", MessageBoxButton.OK, MessageBoxImage.Information);
}
}
}
}
I tend to write my "once-off" timer code like this:
var updaterTimer = new DispatcherTimer();
updaterTimer.Interval = new TimeSpan(0, 0, 0, 0, 300);
EventHandler tick = null;
tick = (s, e) =>
{
updaterTimer.Stop();
updaterTimer.Tick -= tick;
/* execute once-off code here */
};
updaterTimer.Tick += tick;
updaterTimer.Start();
Then I don't need to fluff with making new methods - it's all in one local code block.

Architecture of real-time, iteration application

Sorry for abstract question, but I'm looking for some samples/advices/articles on type of applications which does some equivalent operations in cycle, and every iteration of cycle should expose its result in certain portion of time (for instance, 10 seconds).
My application does synchronization of data between external WCF service and local database. In every iteration an application retrieves changes of data passing request to WCF service and puts changes to database and vice versa. One of most hard requirement for this application is that iterations should fire every ten seconds.
So here is the issues arises. How can I guarantee that iteration will finish for no more than 10 seconds?
I guess this type of applications called real-time applications (in maner of real-time OS).
DAL components that we use acts randomly on connection timeout behavior. So DB operations may take longer time than 10 seconds.
Here is the estimated code of one iteration:
Stopwatch s1 = new Stopwatch();
s1.Start();
Parallel.ForEach(Global.config.databases, new ParallelOptions { MaxDegreeOfParallelism = -1 }, (l) =>
{
Console.WriteLine("Started for {0}", l.key.name);
DB db = new DB(l.connectionString);
DateTime lastIterationTS = GetPreviousIterationTS(l.id);
ExternalService serv = new ExternalService(l.id);
List<ChangedData> ChangedDataDb = db.GetChangedData(DateTime.Now.AddSeconds((lastIterationTS == DateTime.MinValue) ? -300 : -1 * (DateTime.Now - lastIterationTS).Seconds));
List<Data> ChangedDataService = serv.GetModifiedData();
Action syncDBChanges = new Action(() =>
{
// Изменения в БД
foreach (ChangedData d in ChangedDataDb)
{
try
{
// ...
// analyzing & syncing
}
catch (Exception e)
{
logger.InfoEx("Exception_SyncDatabase", e.ToString());
}
}
}
);
Action syncService = new Action(() =>
{
foreach (Data d in ChangedDataService)
{
try
{
// ...
// analyzing & syncing
}
catch (Exception e)
{
logger.InfoEx("Exception_SyncService", e.ToString());
}
}
});
List<WaitHandle> handles = new List<WaitHandle>();
IAsyncResult ar1 = syncDBChanges.BeginInvoke(syncDBChanges.EndInvoke, null);
IAsyncResult ar2 = syncService.BeginInvoke(syncService.EndInvoke, null);
handles.Add(ar1.AsyncWaitHandle);
handles.Add(ar2.AsyncWaitHandle);
WaitHandle.WaitAll(handles.ToArray(), (int)((Global.config.syncModifiedInterval - 1) * 1000));
SetCurrentIterationTS(l.id);
}
catch (Exception e)
{
Console.WriteLine(e.Message);
logger.InfoEx("Exception_Iteration", e.ToString());
continue;
}
}
logger.InfoEx("end_Iteration", IterationContextParams);
}
);
s1.Stop();
Console.WriteLine("Main iteration done for {0}...", s1.Elapsed);
You can consider a couple of options...
Kill the iteration if it exceeds more than 10 seconds and hope that the next iteration can complete process. The issue with this approach is that there is a good possibility that the none of the iterations will complete and therefore the synchronization process will never occur. I would recommend the following option...
If the iteration takes more than 10 seconds, wait for it to complete and skip the next iteration(s). This way you ensure the process completes atleast once. The following is a simplified code sample for reference...
class Updater
{
Timer timer = new Timer();
public object StateLock = new object();
public string State;
public Updater()
{
timer.Elapsed += timer_Elapsed;
timer.Interval = 10000;
timer.AutoReset = true;
timer.Start();
}
void timer_Elapsed(object sender, ElapsedEventArgs e)
{
if (State != "Running")
{
Process();
}
}
private void Process()
{
try
{
lock (StateLock)
{
State = "Running";
}
// Process
lock (StateLock)
{
State = "";
}
}
catch
{
throw;
}
}
}
...
class Program
{
static void Main(string[] args)
{
Updater updater = new Updater();
Console.ReadLine();
}
}
Quartz.net is an excellent scheduler for the .NET platform, which I think could suit your needs.
If you want to kill a job, you can implement IInterruptableJob. You should be able to add some cleanup code in the Interupt method to dispose of any db connections.
If you want finish a job, but only start another job if the last one is completed (which I think is the better option), you can implement IStatefulJob interface
I usually separate the update cycle from the actual timer
The timer does two things:
1) if the update is not running starts it.
2) if the service is already running set a flag for it to continue running.
The update cycle:
1)set running flag
2) do the update
3) set running flag to false
4) if continue running is set go to 1).
You might want to read up on the variety of Timer objects available in .Net: http://msdn.microsoft.com/en-us/magazine/cc164015.aspx
I personally like System.Threading.Timer because you can easily use lambdas, and it allows a state object to be passed if you create a separate callback.
I would also recommend using the System.Threading.Tasks library, because it allows you to gracefully handle cancellations in the case that the timer elapses before your work is completed. Msdn example: http://msdn.microsoft.com/en-us/library/dd537607.aspx
Here's an example of using these components together in a 10 minute timer:
Note: to do this with your sql database you'll need to set Asynchronous Processing=true; and MultipleActiveResultSets=True;
CancellationTokenSource cancelSource = new CancellationTokenSource();
System.Threading.Timer timer = new System.Threading.Timer(callback =>
{
//start sync
Task syncTask = Task.Factory.StartNew(syncAction =>
{
using (SqlConnection conn =
new SqlConnection(
ConfigurationManager.ConnectionStrings["db"].ConnectionString))
{
conn.Open();
using (SqlCommand syncCommand = new SqlCommand
{
CommandText = "SELECT getdate() \n WAITFOR DELAY '00:11'; ",
CommandTimeout = 600,
Transaction = conn.BeginTransaction(),
Connection = conn
})
{
try
{
IAsyncResult t = syncCommand.BeginExecuteNonQuery();
SpinWait.SpinUntil(() =>
(t.IsCompleted || cancelSource.Token.IsCancellationRequested));
if (cancelSource.Token.IsCancellationRequested && !t.IsCompleted)
syncCommand.Transaction.Rollback();
}
catch (TimeoutException timeoutException)
{
syncCommand.Transaction.Rollback();
//log a failed sync attepmt here
Console.WriteLine(timeoutException.ToString());
}
finally
{
syncCommand.Connection.Close();
}
}
}
}, null, cancelSource.Token);
//set up a timer for processing in the interim, save some time for rollback
System.Threading.Timer spinTimer = new System.Threading.Timer(c => {
cancelSource.Cancel();
}, null, TimeSpan.FromMinutes(9), TimeSpan.FromSeconds(5));
//spin here until the spintimer elapses;
//this is optional, but would be useful for debugging.
SpinWait.SpinUntil(()=>(syncTask.IsCompleted || cancelSource.Token.IsCancellationRequested));
if (syncTask.IsCompleted || cancelSource.Token.IsCancellationRequested)
spinTimer.Dispose();
}, null, TimeSpan.FromMinutes(1), TimeSpan.FromMinutes(10));
Perhaps try this. Please make sure you do not create and use any new threads in DoWork() method.
class DatabaseUpdater
{
private readonly Timer _timer;
private List<Thread> _threads;
private readonly List<DatabaseConfig> _dbConfigs;
public DatabaseUpdater(int seconds, List<DatabaseConfig> dbConfigs)
{
_timer = new Timer(seconds * 1000);
_timer.Elapsed += TimerElapsed;
_dbConfigs = dbConfigs;
}
public void Start()
{
StartThreads();
_timer.Start();
}
public void Stop()
{
_timer.Stop();
StopThreads();
}
void TimerElapsed(object sender, ElapsedEventArgs e)
{
StopThreads();
StartThreads();
}
private void StartThreads()
{
var newThreads = new List<Thread>();
foreach (var config in _dbConfigs)
{
var thread = new Thread(DoWork);
thread.Start(config);
newThreads.Add(thread);
}
_threads = newThreads;
}
private void StopThreads()
{
if (_threads == null) return;
var oldThreads = _threads;
foreach (var thread in oldThreads)
{
thread.Abort();
}
}
static void DoWork(object objConfig)
{
var dbConfig = objConfig as DatabaseConfig;
if (null == dbConfig) return;
var n = GetRandomNumber();
try
{
ConsoleWriteLine("Sync started for : {0} - {1} sec work.", dbConfig.Id, n);
// update/sync db
Thread.Sleep(1000 * n);
ConsoleWriteLine("Sync finished for : {0} - {1} sec work.", dbConfig.Id, n);
}
catch (Exception ex)
{
// cancel/rollback db transaction
ConsoleWriteLine("Sync cancelled for : {0} - {1} sec work.",
dbConfig.Id, n);
}
}
static readonly Random Random = new Random();
[MethodImpl(MethodImplOptions.Synchronized)]
static int GetRandomNumber()
{
return Random.Next(5, 20);
}
[MethodImpl(MethodImplOptions.Synchronized)]
static void ConsoleWriteLine(string format, params object[] arg)
{
Console.WriteLine(format, arg);
}
}
static void Main(string[] args)
{
var configs = new List<DatabaseConfig>();
for (var i = 1; i <= 3; i++)
{
configs.Add(new DatabaseConfig() { Id = i });
}
var databaseUpdater = new DatabaseUpdater(10, configs);
databaseUpdater.Start();
Console.ReadKey();
databaseUpdater.Stop();
}

C# - App Crash When Using Ping event

i'm working with ping Librarry in net 3.5 to check the presence of IP.
take a look at the code below:
public void PingIP(string IP)
{
var ping = new Ping();
ping.PingCompleted += new PingCompletedEventHandler(ping_PingCompleted); //here the event handler of ping
ping.SendAsync(IP,"a");
}
void ping_PingCompleted(object sender, PingCompletedEventArgs e)
{
if (e.Reply.Status == IPStatus.Success)
{
//On Ping Success
}
}
Then i execute the code through Thread or backgroundworker.
private void CheckSomeIP()
{
for (int a = 1; a <= 255; a++)
{
PingIP("192.168.1." + a);
}
}
System.Threading.Thread checkip = new System.Threading.Thread(CheckSomeIP);
checkip.Start();
Well, here is the problem:
If i start the thread then i would to close the application (Close with Controlbox at corner), i would get "App Crash"
although i have closed/abort the thread.
I think the problem is event handler? as they still working when i'm closing the Application so that i will get "App Crash"
What would be the best way to solve this case?
I think, on a successfull Ping, you are trying to update the interface from within the Thread, which will cause an CrossThreadingOperation exception.
Search the Web for ThreadSave / delegates:
public void PingIP(string IP)
{
var ping = new Ping();
ping.PingCompleted += new PingCompletedEventHandler(ping_PingCompleted); //here the event handler of ping
ping.SendAsync(IP,"a");
}
delegate void updateTextBoxFromThread(String Text);
void updateTextBox(String Text){
if (this.textbox1.InvokeRequired){
//textbox created by other thread.
updateTextBoxFromThread d = new updateTextBoxFromThread(updateTextBox);
this.invoke(d, new object[] {Text});
}else{
//running on same thread. - invoking the delegate will lead to this part.
this.textbox1.text = Text;
}
}
void ping_PingCompleted(object sender, PingCompletedEventArgs e)
{
if (e.Reply.Status == IPStatus.Success)
{
updateTextBox(Text);
}
}
Also on "quitting" the application, you may want to cancel al running threads. Therefore you need to keep the reference on every thread you start somewhere in your application. in the formClosing-Event of your Main-Form, you can force all (running) threads to stop.

timer in thread problem

I have my application in which in three datagridview independently in three thread load data from wcf service. I execute in each thread timer which every second load this data.
My problem is that every time my thread go threw each thread but only like I show in method timerNowyYork_Elapsed
Any idea why this happens ? I bad lock thread?
this code :
using System;
using System.Collections.Generic;
using System.Linq;
using System.Windows.Forms;
using System.Threading;
namespace Sprawdzanie_warunków_pogodowych
{
public partial class Form1 : Form
{
PogodaEntities entity = new PogodaEntities();
System.Timers.Timer timerKrakow = new System.Timers.Timer();
System.Timers.Timer timerSzczecin = new System.Timers.Timer();
System.Timers.Timer timerNowyYork = new System.Timers.Timer();
KeyValuePair<string, string> krakowInfo;
KeyValuePair<string, string> szczecinInfo;
KeyValuePair<string, string> nowyYorkInfo;
public Form1()
{
System.Net.ServicePointManager.Expect100Continue = false;
InitializeComponent();
List<MiastoContainer> miasta = (from miasto in entity.Miasta
select new MiastoContainer()
{
MiastoName = miasto.Nazwa,
Panstwo = miasto.Państwo
}).ToList();
krakowInfo = new KeyValuePair<string, string>(miasta[0].MiastoName, miasta[0].Panstwo);
szczecinInfo = new KeyValuePair<string, string>(miasta[1].MiastoName, miasta[1].Panstwo);
nowyYorkInfo = new KeyValuePair<string, string>(miasta[2].MiastoName, miasta[2].Panstwo);
ParameterizedThreadStart ptsKrakow = new ParameterizedThreadStart(PobierzKrakow);
Thread tKrakow = new Thread(ptsKrakow);
tKrakow.Start(this.dataGridViewKrakow);
ParameterizedThreadStart ptsSzczecin = new ParameterizedThreadStart(PobierzSzczecin);
Thread tSzczecin = new Thread(ptsSzczecin);
tSzczecin.Start(this.dataGridViewSzczecin);
}
private void oAutorzeToolStripMenuItem_Click(object sender, EventArgs e)
{
new AboutBox1().Show();
}
private void zapiszRaportToolStripMenuItem_Click(object sender, EventArgs e)
{
}
public void PobierzKrakow(object parameters)
{
this.timerKrakow.Elapsed += new System.Timers.ElapsedEventHandler(timerKrakow_Elapsed);
this.timerKrakow.Enabled = true;
this.timerKrakow.Interval = 1000;
this.timerKrakow.Start();
}
public void PobierzSzczecin(object parameters)
{
this.timerSzczecin.Elapsed += new System.Timers.ElapsedEventHandler(timerSzczecin_Elapsed);
this.timerSzczecin.Enabled = true;
this.timerSzczecin.Interval = 1000;
this.timerSzczecin.Start();
}
public void PobierzNowyYork(object parameters)
{
this.timerNowyYork.Elapsed += new System.Timers.ElapsedEventHandler(timerNowyYork_Elapsed);
this.timerNowyYork.Enabled = true;
this.timerNowyYork.Interval = 1000;
this.timerNowyYork.Start();
}
void timerNowyYork_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{ GlobalWeather.Weather weather = new GlobalWeather.Weather();
lock (weather)
{
//thread always start from here
List<object> weatherList = new List<object>();
weatherList.Add(weather.GetTempreature(nowyYorkInfo.Key, nowyYorkInfo.Value));
//and end here , never come any line further
weatherList.Add(weather.GetPressure(nowyYorkInfo.Key, nowyYorkInfo.Value));
weatherList.Add(weather.GetHumidity(nowyYorkInfo.Key, nowyYorkInfo.Value));
weatherList.Add(weather.GetVisibility(nowyYorkInfo.Key, nowyYorkInfo.Value));
entity.SaveChanges();
WarunkiPogodowe warunki = new WarunkiPogodowe()
{
Temperatura = weatherList[0].ToString(),
Ciśnienie = weatherList[1].ToString(),
Wilgotność = weatherList[2].ToString(),
Widoczność = weatherList[3].ToString(),
DataSprawdzenia = DateTime.Now
};
entity.AddToWarunkiPogodowe(warunki);
entity.SaveChanges();
int miastoId = entity.Miasta.First(m => m.Nazwa == nowyYorkInfo.Key).id;
Miasto_has_WarunkiPogodowe m_has_wp = new Miasto_has_WarunkiPogodowe()
{
idMiasto_FK = miastoId,
idWarunkiPogodowe_FK = warunki.id
};
entity.AddToMiasto_has_WarunkiPogodowe(m_has_wp);
entity.SaveChanges();
this.dataGridViewNowyYork.Rows.Add(warunki);
}
}
void timerSzczecin_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
GlobalWeather.Weather weather = new GlobalWeather.Weather();
lock (weather)
{
List<object> weatherList = new List<object>();
weatherList.Add(weather.GetTempreature(szczecinInfo.Key, szczecinInfo.Value));
weatherList.Add(weather.GetPressure(szczecinInfo.Key, szczecinInfo.Value));
weatherList.Add(weather.GetHumidity(szczecinInfo.Key, szczecinInfo.Value));
weatherList.Add(weather.GetVisibility(szczecinInfo.Key, szczecinInfo.Value));
entity.SaveChanges();
WarunkiPogodowe warunki = new WarunkiPogodowe()
{
Temperatura = weatherList[0].ToString(),
Ciśnienie = weatherList[1].ToString(),
Wilgotność = weatherList[2].ToString(),
Widoczność = weatherList[3].ToString(),
DataSprawdzenia = DateTime.Now
};
entity.AddToWarunkiPogodowe(warunki);
entity.SaveChanges();
int miastoId = entity.Miasta.First(m => m.Nazwa == szczecinInfo.Key).id;
Miasto_has_WarunkiPogodowe m_has_wp = new Miasto_has_WarunkiPogodowe()
{
idMiasto_FK = miastoId,
idWarunkiPogodowe_FK = warunki.id
};
entity.AddToMiasto_has_WarunkiPogodowe(m_has_wp);
entity.SaveChanges();
this.dataGridViewSzczecin.Rows.Add(warunki);
}
}
void timerKrakow_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
GlobalWeather.Weather weather = new GlobalWeather.Weather();
lock (weather)
{
List<object> weatherList = new List<object>();
weatherList.Add(weather.GetTempreature(krakowInfo.Key, krakowInfo.Value));
weatherList.Add(weather.GetPressure(krakowInfo.Key, krakowInfo.Value));
weatherList.Add(weather.GetHumidity(krakowInfo.Key, krakowInfo.Value));
weatherList.Add(weather.GetVisibility(krakowInfo.Key, krakowInfo.Value));
entity.SaveChanges();
WarunkiPogodowe warunki = new WarunkiPogodowe()
{
Temperatura = weatherList[0].ToString(),
Ciśnienie = weatherList[1].ToString(),
Wilgotność = weatherList[2].ToString(),
Widoczność = weatherList[3].ToString(),
DataSprawdzenia = DateTime.Now
};
entity.AddToWarunkiPogodowe(warunki);
entity.SaveChanges();
int miastoId = entity.Miasta.First(m => m.Nazwa == krakowInfo.Key).id;
Miasto_has_WarunkiPogodowe m_has_wp = new Miasto_has_WarunkiPogodowe()
{
idMiasto_FK = miastoId,
idWarunkiPogodowe_FK = warunki.id
};
entity.AddToMiasto_has_WarunkiPogodowe(m_has_wp);
entity.SaveChanges();
this.dataGridViewKrakow.Rows.Add(warunki);
}
}
}
class MiastoContainer
{
string miastoName;
public string MiastoName
{
get { return miastoName; }
set { miastoName = value; }
}
string panstwo;
public string Panstwo
{
get { return panstwo; }
set { panstwo = value; }
}
public MiastoContainer()
{ }
public MiastoContainer(string miasto, string panstwo)
{
this.MiastoName = miasto;
this.Panstwo = panstwo;
}
public void Add(MiastoContainer item)
{
((ICollection<MiastoContainer>)this).Add(item);
}
}
}
Your locks are completely useless. As you are locking on an object that you just created, each lock will have it's own identifier and does not affect each other at all.
You need all locks that should exclude each other to use the same object as identifier.
System.Timers.Timer lets you set the SynchronizingObject so that it will invoke the callback on the UI thread. When you create your timers, write:
this.timerKrakow.SynchronizingObject = this;
The timer's elapsed event will then be invoked on the UI thread. That eliminates the need for locks in your event handlers.
You could do the same thing, by the way, with a System.Windows.Forms.Timer, which always invokes the event handler on the UI thread.
The drawback to raising the event on the UI thread is that it might block the user interface. It depends on how much time is spent in the event handler. If your event handler is very quick, then this isn't a problem. If it will take 100 milliseconds to process the event handler, though, you probably don't want to do it on the UI thread.
If you elect not to do it on the UI thread, you need to synchronize access to the UI. The timer event handler can't just modify user interface elements. Instead, you need to call this.Invoke so that any UI modification is done on the UI thread.
I strongly suggest that you NOT use System.Timers.Timer. As the documentation states:
The Timer component catches and
suppresses all exceptions thrown by
event handlers for the Elapsed event.
This behavior is subject to change in
future releases of the .NET Framework.
In other words, if there is a bug in your event handler that throws an exception, you will never know it. I suggest using System.Windows.Forms.Timer or System.Threading.Timer instead.
I don't fully understand your question, but (unless I'm mistaken) the timer callbacks occur in the ThreadPool (or the GUI thread, dependent on usage), so starting them in different threads is pointless.
It seems to me that you are accessing DataGridView directly from another thread. You should not do that. UI controls must always be called from the UI thread. You can use the ISynchronizeInvoke interface to pass the data into correct thread.
this.dataGridViewNowyYork.Invoke(new Action(() => {
this.dataGridViewNowyYork.Rows.Add(warunki);
}), null);

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