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C# append command line output to a Text Box

I'm writing a program (a C# winforms application) to print the console output of a process to a Textbox as follows.
private void button21_Click(object sender, EventArgs e)
{
Process p = new Process();
p.StartInfo.FileName = "node";
p.StartInfo.Arguments = "server.js";
p.StartInfo.UseShellExecute = false;
p.StartInfo.CreateNoWindow = true;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.WorkingDirectory = "D:/Dev/Workspace-JavaScript/p5js/SoftProject1/";
p.OutputDataReceived += new DataReceivedEventHandler(handler);
p.Start();
p.BeginOutputReadLine();
}
private void handler(object sender, DataReceivedEventArgs e)
{
Trace.WriteLine(e.Data);
this.BeginInvoke(new MethodInvoker(() =>
{
textBox1.Text += (e.Data ?? string.Empty)+Environment.NewLine;
}));
}
But when the program is running, It only prints the first line of the console output and nothing more. I have no idea about whats wrong with this code. Can anyone explain what's happening here?

Netsh Commands Cannot Display Correct the result in TextBox

class TcpIpCommands
{
public string Check()
{
Process p = new Process();
p.StartInfo.FileName = #"C:\Windows\syswow64\netsh.exe";
p.StartInfo.Arguments = "int tcp show global";
p.StartInfo.UseShellExecute = false;
p.StartInfo.CreateNoWindow = true;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.StandardOutputEncoding = Encoding.GetEncoding(737);
p.Start();
p.WaitForExit();
return p.StandardOutput.ReadToEnd();
}
public string Command(string FileName, string Arguments)
{
ProcessStartInfo p = new ProcessStartInfo();
p.FileName = FileName;
p.Arguments = Arguments;
p.UseShellExecute = false;
p.CreateNoWindow = true;
p.RedirectStandardOutput = true;
p.StandardOutputEncoding = Encoding.GetEncoding(737);
using (Process process = Process.Start(p))
{
using (StreamReader reader = process.StandardOutput)
{
string result = reader.ReadToEnd();
return result;
}
}
}
public string Reseting()
{
Process p = new Process();
p.StartInfo.FileName = #"C:\Windows\syswow64\netsh.exe";
p.StartInfo.Arguments = #"interface tcp reset";
p.StartInfo.Verb = "runas";
p.StartInfo.UseShellExecute = false;
p.StartInfo.CreateNoWindow = true;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.StandardOutputEncoding = Encoding.GetEncoding(737);
p.Start();
p.WaitForExit();
return p.StandardOutput.ReadToEnd();
}
}
I have an problem with Command Method and Reseting Method. If i try to execute them I receive in RichTextBox the message
set global command failed on ipv4 the parameter is incorrect
But If i run netsh interface tcp show global or hit the Check Method they info me that the status are change.
here are the buttons
private void BtnCheck_Click(object sender, EventArgs e)
{
TcpIpCommands tic = new TcpIpCommands();
richTextBox1.Text = tic.Check();
}
private void btnChimney_Click(object sender, EventArgs e)
{
TcpIpCommands tic = new TcpIpCommands();
richTextBox1.Text = tic.Command(#"C:\Windows\system32\netsh.exe", "interface tcp set global chimney=enabled");
}
private void BtnReset_Click(object sender, EventArgs e)
{
TcpIpCommands tic = new TcpIpCommands();
richTextBox1.Text = tic.Reseting();
}
I cant understand why RichTextBox shows that message but the process execute succefully.
A note. I have try to run the commands with
StartInfo.Verb = "runas";
and both from
C:\Windows\System32\netsh.exe
and
C:\Windows\syswow64\netsh.exe
and i get the same error "set global command failed on ipv4 the parameter is incorrect" but the code execute and the parameter change.

Stopping a continuous Event in C# with (f.ex.) a button

This is probably simple, and the question might not be very good, but I'm looking for the best or most efficient way to accomplish this:
A button click starts an Event, which then runs a method that continiously pings an IP address. The ping output is displayed in a text box.
A click on the same button stops the ping task.
Here's the (I think) relevant code:
The method run by the Event connected to the Ping button:
private void pingClicked (object sender, EventArgs e) {
pinger();
}
The pinger() method:
private void pinger() {
string command = "/c ping " + ipadrtextbox.Text;
if (contchkbox.Checked) {
command += " -t";
}
ProcessStartInfo procStartInfo = new ProcessStartInfo("CMD", command);
Process proc = new Process();
proc.StartInfo = procStartInfo;
proc.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
proc.Start();
procStartInfo.CreateNoWindow = true;
procStartInfo.WindowStyle = ProcessWindowStyle.Hidden;
procStartInfo.RedirectStandardOutput = true;
procStartInfo.UseShellExecute = false;
proc.OutputDataReceived += new
DataReceivedEventHandler(proc_OutputDataReceived);
proc.Start();
proc.BeginOutputReadLine();
procStartInfo.CreateNoWindow = true;
procStartInfo.WindowStyle = ProcessWindowStyle.Hidden;
}
void proc_OutputDataReceived(object sender, DataReceivedEventArgs e) {
if (e.Data != null) {
string newLine = e.Data.Trim() + Environment.NewLine;
MethodInvoker append = () => pingoutput.AppendText(newLine);
pingoutput.BeginInvoke(append);
}
}
A while-loop in the pinger method results in a complaint that "An async read operation has already been started on the stream.", so that's apparently not the way to go.
Also, I haven't found a way for the method to listen for a buttonpress elsewhere in the application, and then stop the task with roc.CancelOutputRead(). But I expect that's the way the task should be stopped?

Keep the running process as a private member of your class then:
private void pingClicked (object sender, EventArgs e) {
if( process != null && !process.HasExited )
{
process.CancelOutputRead()
process.Kill();
process=null;
} else {
pinger();
}
}

Execute multiple command lines with output

I want to perform some command lines to display the result after each input.
Process p = new Process();
ProcessStartInfo info = new ProcessStartInfo();
info.FileName = "cmd.exe";
info.RedirectStandardInput = true;
info.UseShellExecute = false;
p.StartInfo = info;
p.Start();
using (StreamWriter sw = p.StandardInput)
{
if (sw.BaseStream.CanWrite)
{
sw.WriteLine("ftp");
//output
sw.WriteLine("open ftp.server.com");
//output
sw.WriteLine("username");
//output
sw.WriteLine("password");
//output
}
}
Help me to understand how to make the output result after each sw.WriteLine(...)?
Updated
It is not working with ftp. Why?
Initialization:
Test test = new Test();
test.start();
Console.ReadKey();
Class Test:
class Test
{
static StringBuilder StdOutput = new StringBuilder();
Process p = null;
Queue<string> cmdQueue = new Queue<string>();
public void start(){
cmdQueue = new Queue<string>();
cmdQueue.Enqueue("cd c:\\");
cmdQueue.Enqueue("dir");
cmdQueue.Enqueue("ftp");
cmdQueue.Enqueue("open us1.hostedftp.com");
cmdQueue.Enqueue("z3r9#ya.ru");
cmdQueue.Enqueue("123456");
cmdQueue.Enqueue("dir");
setupProcess();
startProcess();
}
private void setupProcess()
{
p = new Process();
ProcessStartInfo info = new ProcessStartInfo();
info.FileName = "cmd";
info.CreateNoWindow = true;
info.RedirectStandardOutput = true;
info.RedirectStandardInput = true;
info.UseShellExecute = false;
p.OutputDataReceived += new DataReceivedEventHandler(OutputDataHandler);
StdOutput = new StringBuilder();
p.StartInfo = info;
}
private async void startProcess()
{
p.Start();
p.BeginOutputReadLine();
using (StreamWriter sw = p.StandardInput)
{
if (sw.BaseStream.CanWrite)
{
while (cmdQueue.Count > 0)
{
string cmd = cmdQueue.Dequeue();
if (cmd != null & cmd != "")
{
await sw.WriteLineAsync(cmd);
Thread.Sleep(100);
//System.Console.WriteLine(StdOutput);
}
else
{
break;
}
}
Console.WriteLine(StdOutput);
}
p.WaitForExit();
}
}
private static void OutputDataHandler(object sendingProcess, DataReceivedEventArgs outLine)
{
if (!String.IsNullOrEmpty(outLine.Data))
{
StdOutput.Append(Environment.NewLine + outLine.Data);
//System.Console.WriteLine(Environment.NewLine + outLine.Data);
}
}
}

I assume that you are actually asking about how to catch outputs from all the commands you want to have executed in the (one) process.
Here is a version of a solution I came up with a long time ago, when I was a rookie here..
The trick is to collect the output as is comes along by listening to events the Process will trigger whenever output gets created: OutputDataReceived and ErrorDataReceived. We need to run things async for this to work, so it will look a little more complicated than the usual examples, which only have one process executing one command..:
First a few variables:
Queue<string> cmdQueue = new Queue<string>();
static StringBuilder StdOutput = new StringBuilder();
static StringBuilder ErrOutput = new StringBuilder();
Process p = null;
Task processTask = null;
bool processIsRunning = false;
Here is a button click event that starts processing all commands from a multiline TextBox. Output gets collected in the two StringBuilders; when the queue is empty, I wait a little longer..:
private void button1_Click(object sender, EventArgs e)
{
cmdQueue = new Queue<string>(tb_commands.Lines.ToList());
setupProcess();
startProcessTask();
while (cmdQueue.Count > 0) Thread.Sleep(100);
Thread.Sleep(500);
tb_out.AppendText(StdOutput + "\r\n" + ErrOutput + "\r\n");
}
Here is the routine that set up the Process. Here we register two events that will notify us when there are lines in the output streams..:
private void setupProcess()
{
p = new Process();
ProcessStartInfo info = new ProcessStartInfo();
info.FileName = "cmd.exe";
info.CreateNoWindow = true;
info.RedirectStandardOutput = true;
info.RedirectStandardError = true;
info.RedirectStandardInput = true;
info.UseShellExecute = false;
p.OutputDataReceived += new DataReceivedEventHandler(OutputDataHandler);
p.ErrorDataReceived += new DataReceivedEventHandler(ErrorDataHandler);
StdOutput = new StringBuilder();
ErrOutput = new StringBuilder();
p.StartInfo = info;
}
After the setup we can start a Task that will start our Process asynchonously..:
private void startProcessTask()
{
var task = Task.Factory.StartNew(() => startProcess());
processTask = task;
}
..and finally here is the async method that after starting the Process and beginning with the asynchronous read operations on the redirected streams, keeps feeding it all lines from the command queue.
private async void startProcess()
{
try { p.Start(); processIsRunning = true; } catch
{
ErrOutput.Append("\r\nError starting cmd process.");
processIsRunning = false;
}
p.BeginOutputReadLine();
p.BeginErrorReadLine();
using (StreamWriter sw = p.StandardInput)
{
if (sw.BaseStream.CanWrite)
do
{
try
{
string cmd = cmdQueue.Dequeue();
if (cmd != null & cmd != "") await sw.WriteLineAsync(cmd);
} catch { }
} while (processIsRunning);
try { p.WaitForExit(); } catch { ErrOutput.Append("WaitForExit Error.\r\n"); }
}
}
The last pieces are the two events we have registered for reading the output from the two streams and adding them to the StringBuilders:
private static void OutputDataHandler(object sendingProcess, DataReceivedEventArgs outLine)
{
if (!String.IsNullOrEmpty(outLine.Data))
{
StdOutput.Append(Environment.NewLine + outLine.Data);
}
}
private static void ErrorDataHandler(object sendingProcess, DataReceivedEventArgs outLine)
{
if (!String.IsNullOrEmpty(outLine.Data))
{
ErrOutput.Append(Environment.NewLine + outLine.Data);
}
}
Note that this works fine for all sorts of commands you can feed into the process, including FTP. Here I change my codepage, show the images I have before, log in to an FTP server, call up the help page, cd and dir, download an image, close the connection and check the images I have now..:
One Caveat: There must be something wrong in the way I wrote this, as VS keeps complaining about a System.InvalidOperationException and the exe file hogs ~10% cpu. Helping me out would be very much appreciated..

Print standard output of Process in event handler

I have a console application which I am running as a process from my C# program.
I have made an event handler to be called when this process terminates.
How do I print the Standard output of this process inside the event handler.
Basically, how do I access the properties of a process inside the event handler ?
My code looks like below.
public void myFunc()
{
.
.
Process p = new Process();
p.StartInfo.FileName = "myProgram.exe";
p.StartInfo.RedirectStandardOutput = true;
p.EnableRaisingEvents = true;
p.Exited += new EventHandler(myProcess_Exited);
p.Start();
.
.
}
private void myProcess_Exited(object sender, System.EventArgs e)
{
Console.WriteLine("log: {0}", <what should be here?>);
}
I do not want to make the process object p as a field of the class.
Also, what is the use of System.EventArgs e field ? How can this be used ?

In your event handler
object sender
is the Process object (that is a pretty common pattern by the way throughout the .NET Framework)
Process originalProcess = sender as Process;
Console.WriteLine("log: {0}", originalProcess.StandardOutput.ReadToEnd());
Note also that you have to set:
p.StartInfo.UseShellExecute = false;
to use IO redirection in your Process.

Use like this:
private void myProcess_Exited(object sender, System.EventArgs e)
{
Process pro = sender as Process;
string output = pro.StandardOutput.ReadToEnd()
Console.WriteLine("log: {0}", output);
}
Standart output is nothing else then StreamReader.

One option would be to capture it in a closure:
public void myFunc()
{
Process p = new Process();
p.StartInfo.FileName = "myProgram.exe";
p.StartInfo.RedirectStandardOutput = true;
p.EnableRaisingEvents = true;
p.Exited += new EventHandler((sender, args) => processExited(p));
p.Start();
}
private void processExited(Process p)
{
Console.WriteLine(p.ExitTime);
}