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What should I change so that Chrome not opens New Window every time when this code triggers

using OpenQA.Selenium;
using OpenQA.Selenium.Chrome;
using OpenQA.Selenium.Support.UI;
using System;
using System.IO;
using System.Threading;
namespace TallyWhatsappsender
{
public class Class1
{
OpenQA.Selenium.IWebDriver chrome_driver = null;
public String InitProcess(String contact,String file_route,String title,String chrome_binary)
{
try
{
if (!System.IO.File.Exists(file_route))
{
return "Error : Attachment not found!";
}
if (!System.IO.File.Exists(System.IO.Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "chromedriver.exe")))
{
return "Error : Chromedriver.exe executable not found!\n chromedriver.exe file is missing\n update or reinstalling may fix the problem";
}
var chrome_driver_service = ChromeDriverService.CreateDefaultService(AppDomain.CurrentDomain.BaseDirectory, "chromedriver.exe");
chrome_driver_service.HideCommandPromptWindow = true;
ChromeOptions chromeOptions = new ChromeOptions();
chromeOptions.UnhandledPromptBehavior = UnhandledPromptBehavior.Accept;
if (File.Exists(chrome_binary))
{
chromeOptions.BinaryLocation = chrome_binary;
}
chrome_driver = new ChromeDriver(chrome_driver_service, chromeOptions);
IJavaScriptExecutor javaScriptExecutor = (IJavaScriptExecutor)chrome_driver;
foreach (string ct in contact.Split(','))
{
if (string.IsNullOrEmpty(ct.Trim()))
{
break;
}
if(ct.Trim().Length != 12)
{
if (!(chrome_driver is null)) chrome_driver.Quit();
return "Error : Invalid contact number-" + ct;
}
chrome_driver.Url = "https://web.whatsapp.com/send?phone=" + ct.Trim();
try
{
chrome_driver.SwitchTo().Alert().Accept();
}
catch (NoAlertPresentException e1)
{
Console.WriteLine(e1.Message);
}
try
{
WebDriverWait wait = new WebDriverWait(chrome_driver, System.TimeSpan.FromSeconds(60));
wait.Until(SeleniumExtras.WaitHelpers.ExpectedConditions.ElementIsVisible(By.XPath("//*[#id='main']/footer/div[1]/div[2]/div/div[2]")));
}
catch (WebDriverTimeoutException)
{
continue;
}
//sending file
IWebElement file_open = chrome_driver.FindElement(By.XPath("//*[#id='main']/footer/div[1]/div[1]/div[2]/div/div/span"));
javaScriptExecutor.ExecuteScript("arguments[0].click();", file_open);
chrome_driver.FindElement(By.CssSelector("input[type='file']")).SendKeys(file_route);
WebDriverWait wait2 = new WebDriverWait(chrome_driver, System.TimeSpan.FromSeconds(30));
wait2.Until(SeleniumExtras.WaitHelpers.ExpectedConditions.ElementIsVisible(By.XPath("//*[#id='app']/div/div/div[2]/div[2]/span/div/span/div/div/div[2]/span/div/div/span")));
IWebElement file_send = chrome_driver.FindElement(By.XPath("//*[#id='app']/div/div/div[2]/div[2]/span/div/span/div/div/div[2]/span/div/div/span"));
javaScriptExecutor.ExecuteScript("arguments[0].click();", file_send);
Thread.Sleep(1000);
//sending text
IWebElement typebox = chrome_driver.FindElement(By.XPath("//*[#id='main']/footer/div[1]/div[2]/div/div[2]"));//:chrome_driver.FindElements(By.CssSelector("div[class ='_3u328 copyable-text selectable-text']"))[0];
typebox.SendKeys(title);
IWebElement text_send = chrome_driver.FindElement(By.XPath("//*[#id='main']/footer/div[1]/div[3]/button/span"));
javaScriptExecutor.ExecuteScript("arguments[0].click();", text_send);
Thread.Sleep(3000);
}
//chrome_driver.Quit();
return "Process finished";
}
//catch (Exception ex)
//{
// if (!(chrome_driver is null)) chrome_driver.Quit();
// return ex.Message;
//}
}
}
}
I am using the above code for exporting a PDF file from tally and send it through Whatsapp Automatically.
I am facing a problem :
Every time I use this option a new tab of chrome opens and closes after sending file, because of new window it asks me to login to whatsapp every time , I think it will sort out if it do not close after sending file or when I activate it , it goes automatically to the previously opened Web.Whatsapp.com so that I will not need authentication each time.
please help me out into this .
Thanks in advance

Every time you call chrome_driver = new ChromeDriver(chrome_driver_service, chromeOptions); a new tab opens.
Try separating the initiating process and the sending process.
For example, your InitProcess method could look like the following:
public InitProcess(String chrome_binary)
{
try
{
if (!System.IO.File.Exists(System.IO.Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "chromedriver.exe")))
{
return "Error : Chromedriver.exe executable not found!\n chromedriver.exe file is missing\n update or reinstalling may fix the problem";
}
var chrome_driver_service = ChromeDriverService.CreateDefaultService(AppDomain.CurrentDomain.BaseDirectory, "chromedriver.exe");
chrome_driver_service.HideCommandPromptWindow = true;
ChromeOptions chromeOptions = new ChromeOptions();
chromeOptions.UnhandledPromptBehavior = UnhandledPromptBehavior.Accept;
if (File.Exists(chrome_binary))
{
chromeOptions.BinaryLocation = chrome_binary;
}
chrome_driver = new ChromeDriver(chrome_driver_service, chromeOptions);
return "Intiated";
}
}
And then you could add a Send function:
public String Send(String contact, String file_route, String title)
{
try
{
IJavaScriptExecutor javaScriptExecutor = (IJavaScriptExecutor)chrome_driver;
foreach (string ct in contact.Split(','))
{
if (string.IsNullOrEmpty(ct.Trim()))
{
break;
}
if(ct.Trim().Length != 12)
{
if (!(chrome_driver is null)) chrome_driver.Quit();
return "Error : Invalid contact number-" + ct;
}
chrome_driver.Url = "https://web.whatsapp.com/send?phone=" + ct.Trim();
try
{
chrome_driver.SwitchTo().Alert().Accept();
}
catch (NoAlertPresentException e1)
{
Console.WriteLine(e1.Message);
}
try
{
WebDriverWait wait = new WebDriverWait(chrome_driver, System.TimeSpan.FromSeconds(60));
wait.Until(SeleniumExtras.WaitHelpers.ExpectedConditions.ElementIsVisible(By.XPath("//*[#id='main']/footer/div[1]/div[2]/div/div[2]")));
}
catch (WebDriverTimeoutException)
{
continue;
}
//sending file
IWebElement file_open = chrome_driver.FindElement(By.XPath("//*[#id='main']/footer/div[1]/div[1]/div[2]/div/div/span"));
javaScriptExecutor.ExecuteScript("arguments[0].click();", file_open);
chrome_driver.FindElement(By.CssSelector("input[type='file']")).SendKeys(file_route);
WebDriverWait wait2 = new WebDriverWait(chrome_driver, System.TimeSpan.FromSeconds(30));
wait2.Until(SeleniumExtras.WaitHelpers.ExpectedConditions.ElementIsVisible(By.XPath("//*[#id='app']/div/div/div[2]/div[2]/span/div/span/div/div/div[2]/span/div/div/span")));
IWebElement file_send = chrome_driver.FindElement(By.XPath("//*[#id='app']/div/div/div[2]/div[2]/span/div/span/div/div/div[2]/span/div/div/span"));
javaScriptExecutor.ExecuteScript("arguments[0].click();", file_send);
Thread.Sleep(1000);
//sending text
IWebElement typebox = chrome_driver.FindElement(By.XPath("//*[#id='main']/footer/div[1]/div[2]/div/div[2]"));//:chrome_driver.FindElements(By.CssSelector("div[class ='_3u328 copyable-text selectable-text']"))[0];
typebox.SendKeys(title);
IWebElement text_send = chrome_driver.FindElement(By.XPath("//*[#id='main']/footer/div[1]/div[3]/button/span"));
javaScriptExecutor.ExecuteScript("arguments[0].click();", text_send);
Thread.Sleep(3000);
return "Process finished";
}
}
}
Now you call InitProcess only once at the beginning of you program and Send every time you want to send the file.

Single instance dotnetcore cli app on linux

I am interested in how to inforce a single instance policy for dotnetcore console apps. To my surprise it seems like there isn't much out there on the topic. I found this one stacko, How to restrict a program to a single instance, but it doesnt seem to work for me on dotnetcore with ubuntu. Anyone here do this before?

Variation of #MusuNaji's solution at: How to restrict a program to a single instance
private static bool AlreadyRunning()
{
Process[] processes = Process.GetProcesses();
Process currentProc = Process.GetCurrentProcess();
logger.LogDebug("Current proccess: {0}", currentProc.ProcessName);
foreach (Process process in processes)
{
if (currentProc.ProcessName == process.ProcessName && currentProc.Id != process.Id)
{
logger.LogInformation("Another instance of this process is already running: {pid}", process.Id);
return true;
}
}
return false;
}

This is a little more difficult on .NET core than it should be, due to the problem of mutex checking on Linux/MacOS (as reported above). Also Theyouthis's solution isn't helpful as all .NET core apps are run via the CLI which has a process name of 'dotnet' which if you are running multiple .NET core apps on the same machine the duplicate instance check will trigger incorrectly.
A simple way to do this that is also multi-platform robust is to open a file for write when the application starts, and close it at the end. If the file fails to open it is due to another instance running concurrently and you can handle that in the try/catch. Using FileStream to open the file will also create it if it doesn't first exist.
try
{
lockFile = File.OpenWrite("SingleInstance.lck");
}
catch (Exception)
{
Console.WriteLine("ERROR - Server is already running. End that instance before re-running. Exiting in 5 seconds...");
System.Threading.Thread.Sleep(5000);
return;
}

Here is my implementation using Named pipes. It supports passing arguments from the second instance.
Note: I did not test on Linux or Mac but it should work in theory.
Usage
public static int Main(string[] args)
{
instanceManager = new SingleInstanceManager("8A3B7DE2-6AB4-4983-BBC0-DF985AB56703");
if (!instanceManager.Start())
{
return 0; // exit, if same app is running
}
instanceManager.SecondInstanceLaunched += InstanceManager_SecondInstanceLaunched;
// Initialize app. Below is an example in WPF.
app = new App();
app.InitializeComponent();
return app.Run();
}
private static void InstanceManager_SecondInstanceLaunched(object sender, SecondInstanceLaunchedEventArgs e)
{
app.Dispatcher.Invoke(() => new MainWindow().Show());
}
Your Copy-and-paste code
public class SingleInstanceManager
{
private readonly string applicationId;
public SingleInstanceManager(string applicationId)
{
this.applicationId = applicationId;
}
/// <summary>
/// Detect if this is the first instance. If it is, start a named pipe server to listen for subsequent instances. Otherwise, send <see cref="Environment.GetCommandLineArgs()"/> to the first instance.
/// </summary>
/// <returns>True if this is tthe first instance. Otherwise, false.</returns>
public bool Start()
{
using var client = new NamedPipeClientStream(applicationId);
try
{
client.Connect(0);
}
catch (TimeoutException)
{
Task.Run(() => StartListeningServer());
return true;
}
var args = Environment.GetCommandLineArgs();
using (var writer = new BinaryWriter(client, Encoding.UTF8))
{
writer.Write(args.Length);
for (int i = 0; i < args.Length; i++)
{
writer.Write(args[i]);
}
}
return false;
}
private void StartListeningServer()
{
var server = new NamedPipeServerStream(applicationId);
server.WaitForConnection();
using (var reader = new BinaryReader(server, Encoding.UTF8))
{
var argc = reader.ReadInt32();
var args = new string[argc];
for (int i = 0; i < argc; i++)
{
args[i] = reader.ReadString();
}
SecondInstanceLaunched?.Invoke(this, new SecondInstanceLaunchedEventArgs { Arguments = args });
}
StartListeningServer();
}
public event EventHandler<SecondInstanceLaunchedEventArgs> SecondInstanceLaunched;
}
public class SecondInstanceLaunchedEventArgs
{
public string[] Arguments { get; set; }
}
Unit test
[TestClass]
public class SingleInstanceManagerTests
{
[TestMethod]
public void SingleInstanceManagerTest()
{
var id = Guid.NewGuid().ToString();
var manager = new SingleInstanceManager(id);
string[] receivedArguments = null;
var correctArgCount = Environment.GetCommandLineArgs().Length;
manager.SecondInstanceLaunched += (sender, e) => receivedArguments = e.Arguments;
var instance1 = manager.Start();
Thread.Sleep(200);
var manager2 = new SingleInstanceManager(id);
Assert.IsFalse(manager2.Start());
Thread.Sleep(200);
Assert.IsTrue(instance1);
Assert.IsNotNull(receivedArguments);
Assert.AreEqual(correctArgCount, receivedArguments.Length);
var receivedArguments2 = receivedArguments;
var manager3 = new SingleInstanceManager(id);
Thread.Sleep(200);
Assert.IsFalse(manager3.Start());
Assert.AreNotSame(receivedArguments, receivedArguments2);
Assert.AreEqual(correctArgCount, receivedArguments.Length);
}
}

The downside of deandob's solution is that one can launch the application from another path. So you may prefer some static path or a tmp path for all users.
Here is my attempt:
//second instance launch guard
var tempPath = Environment.GetEnvironmentVariable("TEMP", EnvironmentVariableTarget.Machine)
??
Path.GetTempPath();
var lockPath = Path.Combine(tempPath, "SingleInstance.lock");
await using var lockFile = File.OpenWrite(lockPath);
here I'm trying to get TEMP system variable at the scope of machine (not the user TEMP) and if its empty - fallback to the user's temp folder on windows or shared /tmp on some linuxes.

.Net DownloadFileTaskAsync robust WPF code

The WPF code below hangs forever when network connection is lost for 3 or more minutes. When connection is restored it neither throws nor continues downloading nor timeouts. If network connection is lost for a shorter period say half a minute, it throws after connection is restored. How can i make it more robust to survive network outage?
using System;
using System.Net;
using System.Net.NetworkInformation;
using System.Windows;
namespace WebClientAsync
{
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
NetworkChange.NetworkAvailabilityChanged +=
(sender, e) => Dispatcher.Invoke(delegate()
{
this.Title = "Network is " + (e.IsAvailable ? " available" : "down");
});
}
const string SRC = "http://ovh.net/files/10Mio.dat";
const string TARGET = #"d:\stuff\10Mio.dat";
private async void btnDownload_Click(object sender, RoutedEventArgs e)
{
btnDownload.IsEnabled = false;
btnDownload.Content = "Downloading " + SRC;
try {
using (var wcl = new WebClient())
{
wcl.Credentials = System.Net.CredentialCache.DefaultNetworkCredentials;
await wcl.DownloadFileTaskAsync(new Uri(SRC), TARGET);
btnDownload.Content = "Downloaded";
}
}
catch (Exception ex)
{
btnDownload.Content = ex.Message + Environment.NewLine
+ ((ex.InnerException != null) ? ex.InnerException.Message : String.Empty);
}
btnDownload.IsEnabled = true;
}
}
}
UPDATE
Current solution is based on restarting Timer in DownloadProgressChangedEventHandler, so the timer fires only if no DownloadProgressChanged events occur within the timeout. Looks like an ugly hack, still looking for a better solution.
using System;
using System.Net;
using System.Threading;
using System.Threading.Tasks;
using System.Windows;
namespace WebClientAsync
{
public partial class MainWindow : Window
{
const string SRC = "http://ovh.net/files/10Mio.dat";
const string TARGET = #"d:\stuff\10Mio.dat";
// Time needed to restore network connection
const int TIMEOUT = 30 * 1000;
public MainWindow()
{
InitializeComponent();
}
private async void btnDownload_Click(object sender, RoutedEventArgs e)
{
btnDownload.IsEnabled = false;
btnDownload.Content = "Downloading " + SRC;
CancellationTokenSource cts = new CancellationTokenSource();
CancellationToken token = cts.Token;
Timer timer = new Timer((o) =>
{
// Force async cancellation
cts.Cancel();
}
, null //state
, TIMEOUT
, Timeout.Infinite // once
);
DownloadProgressChangedEventHandler handler = (sa, ea) =>
{
// Restart timer
if (ea.BytesReceived < ea.TotalBytesToReceive && timer != null)
{
timer.Change(TIMEOUT, Timeout.Infinite);
}
};
btnDownload.Content = await DownloadFileTA(token, handler);
// Note ProgressCallback will fire once again after awaited.
timer.Dispose();
btnDownload.IsEnabled = true;
}
private async Task<string> DownloadFileTA(CancellationToken token, DownloadProgressChangedEventHandler handler)
{
string res = null;
WebClient wcl = new WebClient();
wcl.Credentials = System.Net.CredentialCache.DefaultNetworkCredentials;
wcl.DownloadProgressChanged += handler;
try
{
using (token.Register(() => wcl.CancelAsync()))
{
await wcl.DownloadFileTaskAsync(new Uri(SRC), TARGET);
}
res = "Downloaded";
}
catch (Exception ex)
{
res = ex.Message + Environment.NewLine
+ ((ex.InnerException != null) ? ex.InnerException.Message : String.Empty);
}
wcl.Dispose();
return res;
}
}
}

You need to implement proper timeout for that download. But you don't need to use timer, just use Task.Delay and Task.WaitAny. For example:
static async Task DownloadFile(string url, string output, TimeSpan timeout) {
using (var wcl = new WebClient())
{
wcl.Credentials = System.Net.CredentialCache.DefaultNetworkCredentials;
var download = wcl.DownloadFileTaskAsync(url, output);
// await two tasks - download and delay, whichever completes first
await Task.WhenAny(Task.Delay(timeout), download);
var exception = download.Exception; // need to observe exception, if any
bool cancelled = !download.IsCompleted && exception == null;
// download is not completed yet, nor it is failed - cancel
if (cancelled) {
wcl.CancelAsync();
}
if (cancelled || exception != null) {
// delete partially downloaded file if any (note - need to do with retry, might not work with a first try, because CancelAsync is not immediate)
int fails = 0;
while (true) {
try {
File.Delete(output);
break;
}
catch {
fails++;
if (fails >= 10)
break;
await Task.Delay(1000);
}
}
}
if (exception != null) {
throw new Exception("Failed to download file", exception);
}
if (cancelled) {
throw new Exception($"Failed to download file (timeout reached: {timeout})");
}
}
}
Usage:
const string SRC = "http://ovh.net/files/10Mio.dat";
const string TARGET = #"d:\stuff\10Mio.dat";
// Time needed to restore network connection
TimeSpam TIMEOUT = TimeSpan.FromSeconds(30);
DownloadFile(SRC,TARGET, TIMEOUT); // might want to await this to handle exceptions
Update in response to comment. If you want timeout based on received data, not on whole operation time, it's also possible with Task.Delay. For example:
static async Task DownloadFile(string url, string output, TimeSpan timeout)
{
using (var wcl = new WebClient())
{
wcl.Credentials = System.Net.CredentialCache.DefaultNetworkCredentials;
DateTime? lastReceived = null;
wcl.DownloadProgressChanged += (o, e) =>
{
lastReceived = DateTime.Now;
};
var download = wcl.DownloadFileTaskAsync(url, output);
// await two tasks - download and delay, whichever completes first
// do that until download fails, completes, or timeout expires
while (lastReceived == null || DateTime.Now - lastReceived < timeout) {
await Task.WhenAny(Task.Delay(1000), download); // you can replace 1 second with more reasonable value
if (download.IsCompleted || download.IsCanceled || download.Exception != null)
break;
}
var exception = download.Exception; // need to observe exception, if any
bool cancelled = !download.IsCompleted && exception == null;
// download is not completed yet, nor it is failed - cancel
if (cancelled)
{
wcl.CancelAsync();
}
if (cancelled || exception != null)
{
// delete partially downloaded file if any (note - need to do with retry, might not work with a first try, because CancelAsync is not immediate)
int fails = 0;
while (true)
{
try
{
File.Delete(output);
break;
}
catch
{
fails++;
if (fails >= 10)
break;
await Task.Delay(1000);
}
}
}
if (exception != null)
{
throw new Exception("Failed to download file", exception);
}
if (cancelled)
{
throw new Exception($"Failed to download file (timeout reached: {timeout})");
}
}
}

Personally, if I were to make a robust download solution, I would add a Network connection monitor because that's what we are actually waiting for. For simplicity, something like this will be enough.
online = true;
NetworkChange.NetworkAvailabilityChanged += NetworkChange_NetworkAvailabilityChanged;
_isNetworkOnline = NetworkInterface.GetIsNetworkAvailable();
void NetworkChange_NetworkAvailabilityChanged(object sender, NetworkAvailabilityEventArgs e)
{
online = e.IsAvailable;
}
Then you can actually check for network availability and wait as appropriate before you attempt to download or progress... I will definitely accept that a simple ping solution seems to work better than this at times based on experience.
Depending on the size of what you're downloading, monitoring the network speed may also help so you can decide how to chunk in case of choppy connections. Take a look at this project for ideas.

How to Efficiently Read From a Pipe Stream when using IPC C#

I wrote the simplified version of my program below. Process A launches a child process (Process B). I use an anonymous pipe to write information about the progress of a method running on process B. Meanwhile I have a function in process A that continually reads from a stream to see if there is a new update coming in from the pipe. If there is, the form on process A is updated to reflect the progress. This works as expected, however I am wondering if there is a better way to accomplish this without having to continually check the stream to see if there are any new updates to the progress.
/////////////////
///Process A ////
/////////////////
public void LaunchProcessB()
{
using (AnonymousPipeServerStream pipeServer = new AnonymousPipeServerStream(PipeDirection.In,
HandleInheritability.Inheritable))
{
var _Process = new Process();
_Process.StartInfo.FileName = exeString;
_Process.StartInfo.Arguments = pipeServer.GetClientHandleAsString()
_Process.StartInfo.RedirectStandardOutput = true;
_Process.StartInfo.RedirectStandardInput = true;
_Process.StartInfo.CreateNoWindow = true;
_Process.StartInfo.UseShellExecute = false;
_Process.Start(); //launches process B
pipeServer.DisposeLocalCopyOfClientHandle();
using (StreamReader sr = new StreamReader(pipeServer))
{
try
{
while (true)
{
string temp = sr.ReadLine();
if (temp == null) break;
int result;
if (Int32.TryParse(temp, out result))
ShowDocumentProgress(result);
else ShowProgress(temp);
}
}
catch (Exception)
{
//error occured when reading from stream.
}
}
if (!_Process.Responding && !_Process.HasExited)
{
_Process.Kill();
return;
}
_Process.WaitForExit(10000);
}
}
private void ShowProgressPercent(int percentage)
{
if (percentage > currentPercentage)
{
progressBar.Value = percentage;
}
}
private void ShowProgress(string progressString)
{
labelMessage.Text = progressString;
}
/////////////////
///Process B ////
/////////////////
private StreamWriter _progressWriter;
private PipeStream _progressPipe;
static int Main(string[] args)
{
using (progressPipe = new AnonymousPipeClientStream(PipeDirection.Out, args[0]))
using (_progressWriter = new StreamWriter(_progressPipe))
{
RunLongProcess()
}
}
private void RunLongProcess()
{
//attaches events to PercentProgress and StageProgress methods.
}
private void PercentProgress(int percentage)
{
_progressWriter.WriteLine(percentage.ToString());
_progressPipe.WaitForPipeDrain();
}
private void StageProgress(string stage)
{
_progressWriter.WriteLine(stage);
_progressPipe.WaitForPipeDrain();
}

The while condition is not necessary. Simply read until temp is null. That's the end signal of the stream.
Make this a while(true) loop.
I think you also need to add exception handling to catch the process terminating and severing the pipe. !_Process.HasExited && pipeServer.IsConnected is not enough because it might be true but immediately switch to false after the test.
I also would add a WaitForExit at the end to make sure the system is quiesced before you continue.

Function works when called synchronously, but does not work when called asynchronously

It is my first post on StackOverflow forum so please to be lenient. I have a problem with function which works called synchronously, but doesnot works called asynchronously.
Below You will find function called synchronously:
private void issueInvoices(List<int> lista)
{
foreach (int knh_id in lista)
{
Invoice fs = new Invoice();
fs.FKS_AKCYZA = false;
fs.FKS_CZY_KLON = false;
fs.FKS_DATE = Convert.ToDateTime(MTBDataZapisuDoFK.Text);
fs.NUMBER = knh_id);
}
}
As You can see i passed list to function named issueInvoices list of invoice numbers and in loop i create some invoices.
This function works properly but if i try to call it asynchronously (to display progress bar) my function can not assign to fs.FKS_DATE object dateTime. It looks like static function “Convert.ToDateTime” doesnot work properly. But please take a look on below code where function issueInvoices is called asynchronously…
public delegate void BinaryDelegate(List<int> knh_id);
BinaryDelegate b = new BinaryDelegate(issueInvoices);
IAsyncResult theAsRes = b.BeginInvoke(lista, new AsyncCallback(AddComplete), "Thx U!");
FrmProgressBar fpb=new FrmProgressBar(“Please wait…”);
fpb.Show();
/* below i check how many operation i have to do, if all operations are done, then I close fpb window, program is updating progres bar and in thread make operation issueInvoices*/
while (ilosc_zrobionych != liczbaKontrahentow)
{
fpb.PBStan.Value = (int)((100 * ilosc_zrobionych) / liczbaKontrahentow);
}
fpb.Close();
I put some breakpoints and it looks like program stoping in line, it can conver to datetime, but when i do this synchronously, it works without any errors.
fs.FKS_DATE = Convert.ToDateTime(MTBDataZapisuDoFK.Text);
What could couse this problem and how to resolve it?
Many thanks in advance for reply.
BELOW IS WHOLE CLASS CALLED ASYNCHRONOUSLY:
using System;
using System.Collections.Generic;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using Npgsql;
using Castle.ActiveRecord;
using WFR.Model;
using System.Threading;
namespace Faktury_i_Rachunki_2.Forms
{
public partial class FrmEmisjaFakturPotwierdzonych : FrmBaseForm
{
private ArrayList listaSposobowZaplaty;
public List<int> lista;
private int liczbaWygenerowach;
private int liczbaKontrahentow;
private int ilosc_zrobionych;
private FrmProgressBar fpb;
public delegate void BinaryDelegate(List<int> knh_id);
public FrmEmisjaFakturPotwierdzonych()
{
InitializeComponent();
fpb = new FrmProgressBar("Please wait....");
}
private void BtOK_Click(object sender, EventArgs e)
{
BinaryDelegate b = new BinaryDelegate(WyemitujFakture);
lista.Add(12);
lista.Add(13);
lista.Add(17);
lista.Add(1);
liczbaKontrahentow = lista.Count;
if (TBRejestr.Text.Trim() != "")
{
if (liczbaKontrahentow > 0)
{
liczbaWygenerowach = 0;
ilosc_zrobionych = 0;
WyemitujFakture(lista);
IAsyncResult theAsRes = b.BeginInvoke(lista, new AsyncCallback(AddComplete), "THX");
fpb.Show();
while (ilosc_zrobionych != liczbaKontrahentow)
{
fpb.PBStan.Value = (int)((100 * ilosc_zrobionych) / liczbaKontrahentow);
}
fpb.Close();
}
try
{
MessageBox.Show("Wygenerowano " + liczbaWygenerowach.ToString() + " faktur");
}
catch
{
}
}
}
private void WyemitujFakture(List<int> lista)
{
foreach (int knh_id in lista)
{
try
{
if (luk.Count > 0)
{
FakturySprzedazy fs = new FakturySprzedazy();
fs.FKS_AKCYZA = false;
fs.FKS_CZY_KLON = false;
fs.FKS_DATA_DOW_KS = Convert.ToDateTime(MTBDataZapisuDoFK.Text);
fs.FKS_DATA_FAKTURY = Convert.ToDateTime(MTBDataFaktury.Text);
fs.FKS_DATA_SPRZEDAZY = Convert.ToDateTime(MTBDataSprzedazy.Text);
liczbaWygenerowach++;
}
}
catch (Exception ex)
{
MessageBox.Show("Nie można wyemitować faktury dla kontrahenta o id = " + knh_id.ToString() + " " + ex.Message);
}
ilosc_zrobionych++;
}
}

You are accessing a UI control from a background thread:
MTBDataZapisuDoFK.Text
That is not allowed.
Get this value before calling the method, store it in a variable and send the value as an argument to issueInvoices.

The problem is in getting the value of MTBDataZapisuDoFK.Text (which I assume to be a textbox). Getting or setting the text of a textbox means sending messages to its window. But you keep the UI-thread busy in the while loop and therefore it can not process any messages.
Put a call to Application.DoEvents() into the while loop to allow messages to be processed:
fpb.Show();
while (ilosc_zrobionych != liczbaKontrahentow)
{
Application.DoEvents();
fpb.PBStan.Value = (int)((100 * ilosc_zrobionych) / liczbaKontrahentow);
}
fpb.Close();
I assume that the only reason for calling the method asynchronously is to be able to update the UI during processing the WyemitujFakture-method. Using Application.DoEvents() you do not need asynchonous calls:
fpb = new FrmProgressBar("Please wait....");
fpb.Show();
Application.DoEvents();
WyemitujFakture(lista);
fpb.Close();
You should call Application.DoEvents() after you call fpb.Show() to allow the form to be displayed properly. Also you should instantiate the form in the method itself instead of the constructor, because you can not use the same instance again after calling fpb.Close() (it will be disposed).
Then you can update the progress bar in the WyemitujFakture-method:
private void WyemitujFakture(List<int> lista)
{
foreach (int knh_id in lista)
{
try
{
if (luk.Count > 0)
{
FakturySprzedazy fs = new FakturySprzedazy();
fs.FKS_AKCYZA = false;
fs.FKS_CZY_KLON = false;
fs.FKS_DATA_DOW_KS = Convert.ToDateTime(MTBDataZapisuDoFK.Text);
fs.FKS_DATA_FAKTURY = Convert.ToDateTime(MTBDataFaktury.Text);
fs.FKS_DATA_SPRZEDAZY = Convert.ToDateTime(MTBDataSprzedazy.Text);
liczbaWygenerowach++;
}
}
catch (Exception ex)
{
MessageBox.Show("Nie mozna wyemitowac faktury dla kontrahenta o id = " + knh_id.ToString() + " " + ex.Message);
}
ilosc_zrobionych++;
fpb.PBStan.Value = (int)((100 * ilosc_zrobionych) / liczbaKontrahentow);
Application.DoEvents();
}
}