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Write all of the processes to a text file

I am trying to write all of the processes to a text file, but it will only write the first process in my system. Would you guys mind seeing if there is anything wrong or that I can adjust to fix this issue?
private void button5_Click(object sender, EventArgs e)
{
try
{
var ap = Process.GetProcesses();
SaveFileDialog sfdv2 = new SaveFileDialog();
if(sfdv2.ShowDialog() == DialogResult.OK)
{
foreach(Process process in ap)
{
string path = sfdv2.FileName;
BinaryWriter bw2 = new BinaryWriter(File.Create(path));
bw2.Write("test" + " " + ap.ToString());
bw2.Dispose();
}
}
}
catch(Exception ex) { MessageBox.Show(ex.Message); }
}

Take a step back and see what you are writing.
For each process in the list, you create a file with the same name (and overwrite the previous one) and write "test {process}" in it.
The code does what you tell it, and that's why you end up with only one process in the file.
You can fix this by opening the file outside the loop and closing it afterwards, or even better, you can write it with a using statement. Also, please don't use BinaryWriter for writing to text file. There are many other methods, and the suggested one is StreamWriter. Take a look at this documentation page to see some examples.
string path = sfdv2.FileName;
// with using, the file will be also closed when it's disposed.
using (var file = new System.IO.StreamWriter(path))
{
foreach(Process process in ap)
{
file.WriteLine("test " + ap.ToString());
}
}

You may wish to consider using the Async version of the button click event handler. This is because writing to files is potentially a long running process. So you might want to start it and not wait to block your UI. Combine this with StreamWriter.WriteAsync methods and use in conjunction with await.
e.g.
private async void button5_Click(object sender, EventArgs e)
{
try
{
var ap = Process.GetProcesses();
SaveFileDialog sfdv2 = new SaveFileDialog();
if(sfdv2.ShowDialog() == DialogResult.OK)
{
string path = sfdv2.FileName;
using(StreamWriter bw2 = new StreamWriter(File.Create(path)))
{
foreach(Process process in ap)
{
await bw2.WriteAsync("test" + " " + process.ProcessName.ToString());
}
}
}
}
catch(Exception ex) { MessageBox.Show(ex.Message); }
}

Try splitting the initial problem into smaller, easier tasks:
Lines we want to write down:
var linesToWrite = Process
.GetProcesses()
.Select(process => $"test {process.ProcessName}");
UI:
using (SaveFileDialog dialog = new SaveFileDialog() {
//TODO: here we put dialog's parameters
}) {
if (dialog.ShowDialog() == DialogResult.OK) {
//TODO: here we put the main routine
}
}
Combining it all together:
private void button5_Click(object sender, EventArgs e) {
using (SaveFileDialog dialog = new SaveFileDialog() {
//TODO: here we put dialog's parameters
}) {
if (dialog.ShowDialog() == DialogResult.OK) {
File.WriteAllLines(dialog.FileName, Process
.GetProcesses()
.Select(process => $"test {process.ProcessName}"));
}
}
}

FileSystemWatcher losing files in its queue

I have written a FileSystemWatcher to call a pgm once for every file. But some of my files are lost. I tested the code with only 10-11 files. Deletion of a file is logged correctly, but not the creation. Some of the files are not logged. Is there maybe any problem in my TASK implementation?
or is there any problem with Window Service?
public static FileSystemWatcher m_Watcher;
static BlockingCollection<string> blockingCollection = new BlockingCollection<string>();
protected override void OnStart(string[] args)
{
current_directory = Path.GetDirectoryName(Assembly.GetExecutingAssembly().Location);
//XmlDocument xml = new XmlDocument();
try
{
strDir = ConfigurationManager.AppSettings["Directory"];
fileMask = ConfigurationManager.AppSettings["FileMask"];
strBatfile = ConfigurationManager.AppSettings["Batch"];
strlog = ConfigurationManager.AppSettings["Log"];
m_Watcher = new FileSystemWatcher();
m_Watcher.Filter = fileMask;
m_Watcher.Path = strDir + "\\";
m_Watcher.NotifyFilter = NotifyFilters.LastAccess | NotifyFilters.LastWrite
| NotifyFilters.FileName | NotifyFilters.DirectoryName;
m_Watcher.Created += new FileSystemEventHandler(OnCreated);
m_Watcher.Deleted += new FileSystemEventHandler(OnDeleated);
m_Watcher.Renamed += new RenamedEventHandler(OnRenamed);
m_Watcher.EnableRaisingEvents = true;
}
catch (Exception exception)
{
CustomException.Write(CustomException.CreateExceptionString(exception.ToString()));
}
}
public static void OnDeleated(object source, FileSystemEventArgs e)
{
try
{
Log.getLogger("File deleated- Filename :" + e.Name + " at timestamp : " + DateTime.Now.ToString(), strlog);
}
catch (Exception exception)
{
CustomException.Write(CustomException.CreateExceptionString(exception, e.Name));
}
}
private static void OnCreated(object source, FileSystemEventArgs e)
{
var exceptions = new ConcurrentQueue<Exception>();
try
{
Task.Factory.StartNew(() =>
{
try
{
blockingCollection.Add(e.Name.ToString());
}
catch (Exception)
{
throw;
}
});
Task.Factory.StartNew(() =>
{
try
{
foreach (string value in blockingCollection.GetConsumingEnumerable())
{
System.Diagnostics.Process.Start(Service1.strBatfile);
Log.getLogger("File Processed after executing batch: Filename ->:" + value + " " + "Batch File Executed- > " + Service1.strBatfile + " at timestamp : " + DateTime.Now.ToString(), Service1.strlog);
}
}
catch (Exception)
{
throw;
}
});
}
catch (AggregateException ae)
{
foreach (var ex in ae.InnerExceptions)
{
CustomException.Write(CustomException.CreateExceptionString(ex, e.Name));
}
}
finally
{
m_Watcher.EnableRaisingEvents = true;
}
}

You are using way to many threads/Tasks to get a clear understanding how the code works. As you stated that you want to only process one file at a time you need just one Thread/Task that lives for the lifetime of the class (and I assume the application).
If I strip down your code to accomplish processing one file at a time whenever a file is dropped in a certain folder this could be one implementation.
Notice how I have one ConcurrentQueue and ONE method that reads that queue. I also use the method WaitForExit on the process instance to prevent running more than one process.
static ConcurrentQueue<string> filenames = new ConcurrentQueue<string>();
static void QueueHandler()
{
bool run = true;
AppDomain.CurrentDomain.DomainUnload += (s, e) =>
{
run = false;
filenames.Enqueue("stop");
};
while(run)
{
string filename;
if (filenames.TryDequeue(out filename) && run)
{
var proc = new Process();
proc.StartInfo.FileName = filename;
proc.Start();
proc.WaitForExit(); // this blocks until the process ends....
}
}
}
Now we need a single Task/Thread that will run QueueHandler and our FileSystemWatcher:
protected override void OnStart(string[] args)
{
// have our queue reader method started
Task.Factory.StartNew(QueueHandler);
var fsw = new FileSystemWatcher();
fsw.Created += (o, e) =>
{
// add a file to the queue
filenames.Enqueue(e.FullPath);
// optionally add polling for missed files
// http://stackoverflow.com/questions/239988/filesystemwatcher-vs-polling-to-watch-for-file-changes
};
fsw.Path = ConfigurationManager.AppSettings["Directory"];
fsw.NotifyFilter = NotifyFilters.FileName;
fsw.Filter = ConfigurationManager.AppSettings["FileMask"];
fsw.EnableRaisingEvents = true;
}
This implementation will use at worst three threads: one main thread, one for the Created events of the FileSystemWatcher and one for the QueueHandler instead if your example code where new Tasks were started every time a new file was created in the folder the FileSystemWatcher was watching

You are starting two tasks in your OnCreated method, where the second task seems to depend on the output from the first task. However, there is no guarantee that the first task will have finished (or even started) when the second task executes.
You could group the two operations into a single task, which would then execute sequentially, or you could await the result of the first task.
There is also a lot of information missing from your code. It clearly isn't the 'real' code because OnDeleated [sic] is misspelled and wouldn't compile. We also can't see what your external process is or how you are attempting to pass the file list to it. There could be lots of problems there. Would it be possible to post the actual code?

How do I report progress to the GUI from a list of Tasks?

I'm currently working on a program that converts a list of files from .ps (PostScript) to .png.
Originally, this was done in a batch file, one file at a time. I am working on code that uses the Ghostscript.NET dll to process these files asynchronously. By splitting these up into tasks, I have cut down the processing time from 30 minutes to about 6 minutes.
I want to be able to show the user some sort of progress on this, so that it doesn't just look like my program is frozen.
I know just enough about threading to frustrate myself, so any suggestions on the best way to do this is greatly appreciated. The code below has a BackgroundWorker implemented to try to show the progress. I have used BGWorker before to show progress, but not on multiple tasks like this. In fact, this is my first time multi-threading without just using BGWorker.
I feel that BGWorker is probably not what I need to be using, but I wanted to try to take a stab at it myself before I asked.
Here is the code that I have so far:
public partial class ProcessStatusForm : Form
{
public string[] testList;
public string wordPath;
public string StatusText;
public GhostscriptVersionInfo _gs_version_info;
public DirectoryInfo dInfo;
public List<Task> tasks;
public float NumberOfTasks;
public bool PS2PNGRunning;
public int ProgressPct;
public float dPercent;
public decimal decPercent;
public ProcessStatusForm(string wordDoc, List<string> runList)
{
InitializeComponent();
this.wordPath = wordDoc;
this.testList = runList.ToArray();
this.StatusText = string.Empty;
this._gs_version_info = GhostscriptVersionInfo.GetLastInstalledVersion(GhostscriptLicense.GPL |
GhostscriptLicense.AFPL, GhostscriptLicense.GPL);
this.dInfo = new DirectoryInfo(SettingsClass.PSFolder);
this.PS2PNGRunning = false;
this.ProgressPct = 0;
this.NumberOfTasks = runList.Count;
}
private void ProcessStatusForm_Shown(object sender, EventArgs e)
{
//Spawn tasks for each of the .ps files in the PS_FILES folder
tasks = new List<Task>(dInfo.GetFiles("*.ps").Length);
//Start the BackgroundWorker
this.PS2PNGRunning = true;
BackgroundWorker.RunWorkerAsync();
foreach (var file in dInfo.GetFiles("*.ps"))
{
//Get fileName to pass fo the ConvertPS2PNG
string inputFile = file.Name;
//Create the Task
var task = Task.Factory.StartNew(() => ConvertPS2PNG(inputFile));
tasks.Add(task);
}
//Wait until all tasks have completed
Task.WaitAll(tasks.ToArray());
PS2PNGRunning = false;
}
private void ConvertPS2PNG(string input)
{
string output = input.Replace(".ps", "_01.png");
input = SettingsClass.PSFolder + input;
output = SettingsClass.PNGFolder + output;
GhostscriptProcessor processor = new GhostscriptProcessor(_gs_version_info, true);
processor.Process(CreateGSArgs(input, output), new ConsoleStdIO(true, true, true));
}
private void BackgroundWorker_DoWork(object sender, DoWorkEventArgs e)
{
ProgressPct = 0;
while (PS2PNGRunning)
{
Thread.Sleep(1000);
float TasksCompleted = 0;
foreach (var tsk in tasks)
{
if (tsk.Status == TaskStatus.RanToCompletion)
{
TasksCompleted++;
}
}
StatusText = TasksCompleted + " of " + NumberOfTasks + " converted...";
dPercent = TasksCompleted / NumberOfTasks;
dPercent *= 100;
decPercent = (decimal)dPercent;
decPercent = Math.Round(decPercent);
ProgressPct = (int)decPercent;
BackgroundWorker.ReportProgress(ProgressPct);
}
BackgroundWorker.ReportProgress(100);
}
private void BackgroundWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
this.ProgressLabel.Text = this.StatusText;
this.progressBar.Style = ProgressBarStyle.Continuous;
this.progressBar.Value = e.ProgressPercentage;
}
public string[] CreateGSArgs(string inPath, string outPath)
{
List<string> gsArgs = new List<string>();
gsArgs.Add("-dBATCH");
gsArgs.Add("-dNOPAUSE");
gsArgs.Add("-sDEVICE=png16m");
gsArgs.Add("-dQUIET");
gsArgs.Add("-sPAPERSIZE=letter");
gsArgs.Add("-r800");
gsArgs.Add("-sOutputFile=" + outPath);
gsArgs.Add(inPath);
return gsArgs.ToArray();
}
}
When I put breaks in the code of BackgroundWorker_DoWork, everything seems to be coming out right, but when it gets to the BackgroundWorker.ReportProgress(), it never makes it to the BackgroundWorker_ProgressChanged() method.
At the very least, I could live with just having a progressBar.Style as marquee while this is running so that the user can see that the program is working, but reporting the actual progress would be ideal.
As I said before, I haven't done a ton of work with threading, and all of my knowledge on the subject pretty much comes from Google and StackOverflow. If there is a completely different way to do this, I am open to all criticism.

Was the name BackgroundWorker given to the object when you dragged it from the designer screen? If not change your code to use the appropriate name it was given (default should have been backgroundWorker1).
Or...
Try casting the sender object to a BackgroundWorker object in your DoWork method and call ReportProgress() from there.
private void BackgroundWorker_DoWork(object sender, DoWorkEventArgs e)
{
BackgroundWorker bw = sender as BackgroundWorker;
if (bw != null)
{
bw.ReportProgress(25);
}
}

C# Progressbar & Textbox Not Updating

I've seen some great answers here and was wondering if someone could help me out.
Here's my code:
namespace expandGUIWPF
{
public static string getSHA256b64(string filepath)
{
byte[] bytes = SHA256.Create().ComputeHash(File.ReadAllBytes(filepath));
return Convert.ToBase64String(bytes);
}
private void btnRun_Click(object sender, RoutedEventArgs e)
{
{
string folder = txtFolder.Text;
string filelist = folder + "\\FileList.txt";
string[] test = Directory.GetFiles(folder, "*", System.IO.SearchOption.AllDirectories);
File.WriteAllLines(filelist, test);
int length = File.ReadLines(filelist).Count();
pBar1.Minimum = 1;
pBar1.Maximum = length;
File.WriteAllLines(filelist, test);
using (StreamReader sr = new StreamReader(filelist))
{
string line;
while ((line = sr.ReadLine()) != null)
{
string oldfile = line;
string newfile = oldfile + ".expanded";
string oldhash = "";
string newhash = "";
try
{
ProcessStartInfo startInfo = new ProcessStartInfo(#"C:\test\test.exe", oldfile + " " + newfile);
startInfo.WindowStyle = ProcessWindowStyle.Hidden;
Process.Start(startInfo);
Thread.Sleep(1000);
if (File.Exists(oldfile))
{
oldhash = getSHA256b64(oldfile);
}
if (File.Exists(newfile))
{
newhash = getSHA256b64(newfile);
File.Delete(oldfile);
File.Move(newfile, oldfile);
}
pBar1.Value = pBar1.Value + 1;
txtLog.AppendText(oldfile + "\r\n Old: " + oldhash + "\r\n New: " + newhash + "\r\n");
if (!(oldhash == newhash))
{
txtLog.AppendText("Successfully expanded file \r\n");
}
else
{
txtLog.AppendText("Unable to expand file \r\n");
}
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString());
}
}
}
}
}
}
}
The problem is that my progressbar isn't updating. I know a little C# but I'm a beginner to WPF and can't get my head around setting up a background worker to update my UI. Would someone be able to give me a few pointers please? Currently the app works fine, but the progressbar jumps to 100% finished and all of the text suddenly appears.
Thanks in advance!
Tom

First you'll want your background worker to handle the processes in its DoWork event. Within that event you can call the ProgressChanged event to update the progress bar. Below is an example:
private void btnRun_Click(object sender, RoutedEventArgs e)
{
if(workerThread.IsBusy == false) // Make sure someone doesn't click run multiple times by mistake
{
pBar1.Value = 0;
workerThread.RunWorkerAsync();
}
}
private void workerThread_DoWork(object sender, DoWorkEventArgs e)
{
// Definitions and so forth
pBar1.Minimum = 0;
pBar1.Maximum = length;
int status = 0;
using (StreamReader sr = new StreamReader(filelist))
{
string line;
while ((line = sr.ReadLine()) != null)
{
// Try/Catch work here
status++;
workerThread.ReportProgress(status);
}
}
private void workerThread_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
pBar1.Value = e.ProgressPercentage;
}

Just understand that the thread that's running the Form is the same one that will be used to update the form's controls. So if you have 'stuff' to do - like encrypting / decrypting lines from a file - you need to perform those items on another thread with a callback, otherwise the form display wont update until it's done with your stuff to do. You can raise events from inside a worker thread -- and catch them using an event handler on the main (form) thread to update the progress bar.

It seems that your UI thread is being blocked, in windows forms programming you have one message pump and while you main thread (UI) is doing something else it has to wait before it can process messages. You can fix this problem by setting up a background worker to send updates
For more information on UI thread and the message pump see this
http://www.codeproject.com/Articles/10311/What-s-up-with-BeginInvoke
For infomation on the backgroundworker thread see this
http://msdn.microsoft.com/en-us/library/system.componentmodel.backgroundworker.aspx
Small Example code
// This event handler is where the time-consuming work is done.
private void backgroundWorker1_DoWork(object sender, DoWorkEventArgs e)
{
BackgroundWorker worker = sender as BackgroundWorker;
for (int i = 1; i <= 10; i++)
{
if (worker.CancellationPending == true)
{
e.Cancel = true;
break;
}
else
{
// Perform a time consuming operation and report progress.
System.Threading.Thread.Sleep(500);
worker.ReportProgress(i * 10);
}
}
}

Update ui thread

I have a ListBox which I put some files, if the file is not AVI I automatically converts it but I want when the files converting message will write on a label that the files are now converted to another format, i know i need use Dispatcher in order to update the UI thread but i use now Winform instead of WPF, and i need help with this.
BTW i cannot use Task because i am using .Net 3.5
private void btnAdd_Click(object sender, EventArgs e)
{
System.IO.Stream myStream;
OpenFileDialog thisDialog = new OpenFileDialog();
thisDialog.InitialDirectory = "c:\\";
thisDialog.Filter = "All files (*.*)|*.*";
thisDialog.FilterIndex = 1;
thisDialog.RestoreDirectory = false;
thisDialog.Multiselect = true; // Allow the user to select multiple files
thisDialog.Title = "Please Select Source File";
thisDialog.FileName = lastPath;
List<string> list = new List<string>();
if (thisDialog.ShowDialog() == DialogResult.OK)
{
foreach (String file in thisDialog.FileNames)
{
try
{
if ((myStream = thisDialog.OpenFile()) != null)
{
using (myStream)
{
listBoxFiles.Items.Add(file);
lastPath = file;
}
}
}
catch (Exception ex)
{
MessageBox.Show("Error: Could not read file from disk. Original error: " + ex.Message);
}
}
for (int i = 0; i < listBoxFiles.Items.Count; i++)
{
string path = (string)listBoxFiles.Items[i];
FileInfo fileInfo = new FileInfo(path);
if (fileInfo.Extension != ".AVI")
{
listToRemove.Add(path);
}
}
(new System.Threading.Thread(sendFilesToConvertToPcap)).Start();
foreach (string file in listToRemove) //remove all non .AVI files from listbox
{
listBoxFiles.Items.Remove(file);
}
}
}
this function need to change the Label:
public void sendFilesToConvertToPcap()
{
if (listToRemove.Count == 0) // nothing to do
{
return;
}
lblStatus2.Content = "Convert file to .AVI...";
foreach (String file in listToRemove)
{
FileInfo fileInfo = new FileInfo(file);
myClass = new (class who convert the files)(fileInfo);
String newFileName = myClass.mNewFileName;
listBoxFiles.Items.Add(myClass._newFileName);
}
lblStatus2.Content = "Finished...";
}

From your question, it seems that you'd like to convert several files. You may want to consider using the BackgroundWorker class and overwrite the DoWork and ProgressChanged events as described in this article. You can update the label and other controls in the ProgressChanged event.

public void sendFilesToConvertToPcap()
{
.....
....
this.Invoke((MethodInvoker)delegate {
lblStatus2.Text = "Convert file to .AVI..."; });
....
}

This is a very common requirement for long-running processes. If you don't explicitly call methods on a separate thread, they will automatically run on the main (see: UI) thread and cause your UI to hand (as I suspect you already know).
http://www.dotnetperls.com/backgroundworker
Here is an old, but excellent link with an example on how to use the background worker to handle the threadpool for you.
This way, you can just create a worker to manage running your conversion process on a separate thread, and I believe there is even an example for creating a process bar.