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process.Start() not working in C# to call python script

Sorry if this is something obvious, I'm super new to C#.
I'm working on a program that runs a python script to check something online, that then writes it back to a file that C# reads and puts on a form. Everything works if I manually run them both at the same time, but I really want to start the script from the C# program.
Here's the function that should start the python script:
private void RunPython()
{
Process p = new Process();
ProcessStartInfo startInfo = new ProcessStartInfo();
startInfo.WindowStyle = ProcessWindowStyle.Hidden;
startInfo.FileName = "cmd.exe";
startInfo.Arguments = "python " + path + "\\foo.py";
p.StartInfo = startInfo;
p.Start();
}
private void Button_Click(object sender, RoutedEventArgs e)
{
// get things set up... etc.
RunPython();
}
I've tried running it without the window hidden, and it just brings up an empty cmd line in the 'path' directory. Is it never running the python script? It doesn't seem like it is, but it may also be running it and immediately closing it. I can't tell.
I need it to stay open for the duration of the C# program's run, so if the problem is it exiting when the RunPython() method returns, is there some different way I could go about this?
Thanks!!

If you want to run a program in the command line using arguments to cmd.exe you need the /c flag. Alternatively you can use /k but that keeps the command process running which you probably don't want.
/c Carries out the command specified by String and then stops.
So it's usage is cmd.exe /c [string]
Try changing your arguments line to:
startInfo.Arguments = "/c \"python " + path + "\\foo.py\"";
See here for more information about running cmd.exe and dealing with quotes in the string section of the command: https://technet.microsoft.com/en-us/library/cc771320(v=ws.11).aspx

problems with stdout and psexec.exe from sysinternals

i have searched and read about issues with psexec.exe from sysinternals not working properly with c# and stdout. i am now trying to figure out how to just call a batch file that has the following instead of using System.Diagnostics.Process to call psexec:
test.bat contains the following line:
psexec.exe \\hostname -u user -p password ipconfig /all >c:\test.txt
test.txt will be saved on the host where i am running my c sharp app and executing psexec.
when i execute the following:
System.Diagnostics.Process psexec_run = new System.Diagnostics.Process();
psexec_run.StartInfo.FileName = "cmd.exe";
psexec_run.StartInfo.Arguments = #"/c """ + cur_dir + #"\test\test.bat""";
psexec_run.StartInfo.UseShellExecute = false;
psexec_run.Start();
psexec_run.WaitForExit();
i see the cmd window pop up and it runs something but not sure what and goes away.
if i execute the following:
System.Diagnostics.Process psexec_run = new System.Diagnostics.Process();
psexec_run.StartInfo.FileName = cur_dir + "\\test\\psexec.exe";
psexec_run.StartInfo.Arguments = #"\\hostname -u user -p password ipconfig /all";
psexec_run.StartInfo.UseShellExecute = false;
psexec_run.Start();
psexec_run.WaitForExit();
then i see the command window open and it runs psexec which takes quite a few secs and i quickly see my output i need, but i have no way of capturing the output or writing it to a file.
i guess my issue now is since psexec will not work with stdout how can i capture the output from the psexec command to write it to a file???
see the following link for the issues with psexec, the last reply on this url mentioned a way to write the process output to a file without using stdout, i'm newbie to c# i can't figure out how to write process output without use stdout :(
http://forum.sysinternals.com/psexec-fails-to-capture-stdout-when-launched-in-c_topic19333.html
based on response below i tried the following:
ProcessStartInfo psi = new ProcessStartInfo(cur_dir + "\\test\\psexec.exe", #"\\hostname -u user -p password ipconfig /all");
psi.RedirectStandardOutput = true;
psi.RedirectStandardError = true;
psi.UseShellExecute = false;
Process p = Process.Start(psi);
StreamReader myStreamReader = p.StandardOutput;
// Read the standard output of the spawned process.
string sOutput = myStreamReader.ReadToEnd();
i did ReadToEnd so i would make sure it got all the output, it DID NOT!! for some reason it only go the first line of ipconfig output that was it. Also the cmd window it opened up never closed for some reason. even with CreateNoWindow=true the code just hangs. so again something is wrong with psexec and stdout i think?? as i can run this code just fine using ipconfig /all command on the local host and not use psexec...
again i am looking to avoid stdout and somehow find a way to get the output from this command or unless there is something else i'm over looking? also, not to make more work for anyone, but if you d/l psexec.exe from sysinternals and test it with a command on a remote host you will see. i have spent 2 days on this one :( trying to figure out how to use psexec or find some other quick method to execute remote command on a host and get ouptput.
UPDATE:
i gave up on psexec in c# code, i saw many posts about psexec eating the output, having a child window process ,etcc
until my head hurt :) so i am trying to run a batch file and output to a file and it's not making sense...
i have a batch file test.bat with the following
psexec.exe \\\hostname -u name -p password ipconfig /all >c:\test.txt
when i run the following code:
ProcessStartInfo psi = new ProcessStartInfo(cur_dir + #"\test\test.bat");
psi.RedirectStandardOutput = true;
psi.RedirectStandardError = true;
psi.UseShellExecute = false;
Process p = Process.Start(psi);
p.WaitForExit();
the cmd windows comes and goes really quickly and the test.txt file is created but is 0 bytes no info in it.
so if i run the batch file in a windows cmd line with the psexec command it works perfectly fine!!???
so then to verify psexec was the issue i changed the batch file to:
ipconfig /all >c:\test.txt
i execute my code above and it works fine creates the output in the test.txt file..???!!!!
why is not working with psexec am i missing something? if it's psexec, does anyone have
any recommendations for how i can execute a command on a remote windows host and get me the
output???

I have an answer to this problem that has worked for me.
Hopefully someone else will find it useful.
I have literally just spent the last two hours tearing my hair out with this. The psexec tool runs completely fine using a normal command prompt but when attempting to redirect the streams it truncates the output and you only get half output back.
In the end how I fixed my issue was a little bit of a hack. I piped the output of the command to a text file and read it back in to return it from the function.
I also has to set UseShellExecute to true. Without this it still wouldn't work. This had the unfortunate side effect of showing the console window. To get around that I set the window style to be hidden and hey presto it works!!!
Heres my code:
string ExecutePSExec(string command)
{
string result = "";
try
{
string location = AppDomain.CurrentDomain.BaseDirectory;
// append output to file at the end of this string:
string cmdWithFileOutput = string.Format("{0} >{1}temp.log 2>&1", command,location );
// The flag /c tells "cmd" to execute what follows and exit
System.Diagnostics.ProcessStartInfo procStartInfo = new System.Diagnostics.ProcessStartInfo("cmd", "/c " + cmdWithFileOutput);
procStartInfo.UseShellExecute = true; // have to set shell execute to true to
procStartInfo.CreateNoWindow = true;
procStartInfo.WindowStyle = ProcessWindowStyle.Hidden; // as a window will be created set the window style to be hiddem
System.Diagnostics.Process proc = new System.Diagnostics.Process();
proc.StartInfo = procStartInfo;
proc.Start();
proc.WaitForExit();
// now read file back.
string filePath = string.Format("{0}temp.log", location);
result = System.IO.File.ReadAllText(filePath);
}
catch (Exception objException)
{
// Log the exception
}
return result;
}
and its usage:
string command = #"psexec.exe -l -u domain\username -p password /accepteula \\192.168.1.3 netstat -a -n";
ExecutePSExec(command);

I had exactly same problem. i was getting "Windows ip config. " as first line when i run with psexec. i tried with paexec it worked well. I used Marius's code.
Note: if you dont use first cmd / c in arguments command runs only on local computer even if you define target as \\remoteserver
ProcessStartInfo psi = new ProcessStartInfo("cmd.exe");
psi.Arguments = #"cmd/c C:\paexec.exe \\\192.168.2.5 -s -u test.local\administrator -p Password1 cmd /c ipconfig";
psi.CreateNoWindow = true;
psi.RedirectStandardOutput = true;
psi.RedirectStandardError = true;
psi.UseShellExecute = false;
Process p = Process.Start(psi);
System.IO.StreamReader myStreamReader1 = p.StandardOutput;
p.WaitForExit();
string sOutput = myStreamReader1.ReadToEnd();

Are you sure your sourcecode is correct? that link is quite a bit old.. maybe its fixed!
Heres an example how to redirect the standard-output and put whole output in a string via streamreader:
ProcessStartInfo psi = new ProcessStartInfo("tftp.exe");
// preferences for tftp process
psi.CreateNoWindow = true;
psi.RedirectStandardOutput = true;
psi.RedirectStandardError = true;
psi.UseShellExecute = false;
Process p = Process.Start(psi);
StreamReader myStreamReader = p.StandardOutput;
p.WaitForExit();
// Read the standard output of the spawned process.
string sOutput = myStreamReader.ReadToEnd();

i found a solution. apparently psexec is NOT going to work in c sharp. so i came up with some wmi code to connect to a remote host and it's working PERFECTLY!!! :)
i used microsoft's WMICodeCreator.exe to create wmi code for C# for the process method on a remote host, wow that tool is amazing because wmi code is little confusing to me.

psexec's output goes to StandardError and not StandardOutput. I don't know why it is that way. Following code snippet access it.
ProcessStartInfo startInfo = new ProcessStartInfo();
startInfo.RedirectStandardError = true;
Process process = new Process();
process.StartInfo = startInfo;
process.Start();
process.WaitForExit();
errors = process.StandardError.ReadToEnd();
process.Close();

why WaitForExit() doesn't wait?

i am adding Custom Action into my VS2008 setup project (MSI installer).
I am calling a batch file to create database and want to delete those files after. I have WaitForExit() but it will not wait. Why?
ProcessStartInfo startInfo = new ProcessStartInfo();
startInfo.UseShellExecute = false;
string tempDir = #"C:\Temp\";
startInfo.FileName = tempDir + "sybaseDB\\en_AllInOne_installDB.bat";
startInfo.Arguments = tempDir + "sybaseDB\\";
try
{
Process startDB = Process.Start(startInfo);
startDB.WaitForExit();
}
catch (Exception e)
{
//do something?
}
finally {
System.IO.File.Delete(tempDir);
}
no difference with startInfo.UseShellExecute = true;
The batch was executed without any problem because it require user input and I input y and n for questions. but that delete action happened before my input. And I have a pause at the end of the batch file. I can watch the process of the batch file going.
EDIT:
I tested more than 10 times, it didn't work. After lunch, I put one more waitForExit and a while loop with HasExited check. it will sleep inside the while loop. I found it worked. Then I deleted those extra code, back to one WaitForExit. It seems work now.

This is probably throwing an exception because you can't execute a .bat file. You probably intend to execute cmd.exe by giving the .bat file as a command line argument.

Hide Command Window in C# Application

Before you say its a duplicate question, please let me explain (as I've read all similar threads).
My application has both of these settings:
procStartInfo.CreateNoWindow = true;
procStartInfo.WindowStyle = ProcessWindowStyle.Hidden;
and is also has WindowsApplication as the output type.
The black window STILL comes up when I call a command line command. Is there anything else I can do to hide the window? It doesn't happen for all commands, XCOPY is a situation where it the black window does flash up. This only happens though when the destination I'm XCOPYing too already contains the file and it's prompting me if I want to replace it. Even if I pass in /Y it will still flash briefly.
I'm open to using vbscript if that will help, but any other ideas?
The client will call my executable and then pass in a command line command ie:
C:\MyProgram.exe start XCOPY c:\Test.txt c:\ProgramFiles\
Here's the full code of the application:
class Program
{
static void Main(string[] args)
{
string command = GetCommandLineArugments(args);
// /c tells cmd that we want it to execute the command that follows and then exit.
System.Diagnostics.ProcessStartInfo procStartInfo = new System.Diagnostics.ProcessStartInfo("cmd.exe", "/c " + command);
procStartInfo.RedirectStandardOutput = true;
procStartInfo.UseShellExecute = false;
// Do not create the black window.
procStartInfo.CreateNoWindow = true;
procStartInfo.WindowStyle = ProcessWindowStyle.Hidden;
System.Diagnostics.Process process = new System.Diagnostics.Process();
process.StartInfo = procStartInfo;
process.Start();
}
private static string GetCommandLineArugments(string[] args)
{
string retVal = string.Empty;
foreach (string arg in args)
retVal += " " + arg;
return retVal;
}
}

The problem is that you're using cmd.exe. Only its console window will be hidden, not the console window for the process you ask it to start. There's little point in using cmd.exe, unless you are trying to execute some of the commands it implements itself. Like COPY.
You can still suppress the window if you need cmd.exe, you'll have to use the /B option for Start. Type start /? at the command prompt to see options. Not that it helps, you can't use START COPY.
There's a specific quirk in xcopy.exe that might throw you off as well. It does not execute if you don't also redirect the input. It just fails to run without diagnostic.

i see that you are calling cmd and then passing the command as parameters. Instead call the command directly
e.g.
System.Diagnostics.ProcessStartInfo procStartInfo = new System.DiagnosticsProcessStartInfo("xcopy", "<sourcedir> <destdir> <other parameters>");
procStartInfo.WindowStyle = ProcessWindowStyle.Hidden;

You can try adding
process.StartInfo.UseShellExecute = false;
to your process

If you are calling cmd.exe in your C# code and passing the commands to it via standard input.WriteLine and you don't want your CMD window to pop up every time you run your code, you can simply write this command:
test.StartInfo.FileName = "cmd.exe";
test.StartInfo.CreateNoWindow = true;
By setting create no window to false, we are running the command sent to the CMD in the background and the output is not being displayed to the user. By setting it to false, the CMD window pops up.

I had a similar task - It is possible to hide the window after creation via an API call.
(In your case you maybe need a helper thread.)
[DllImport("user32.dll")]
static extern bool ShowWindow(IntPtr hWnd, int nCmdShow);
If you know the handle of the new Window you can call
ShowWindow(hWnd, 0);
0 hides the window, 1 shows the window
To get the handle of the Window take a look at:
pinvoke.net enumwindows(user32)

RedirectStandardInput crashes program

the following code is to open a console application (which uses pdcurses for output, nothing special):
myProcess.StartInfo.FileName = "some.exe";
myProcess.StartInfo.UseShellExecute = false;
myProcess.StartInfo.CreateNoWindow = false;
myProcess.StartInfo.RedirectStandardInput = true;
myProcess.Start();
The Problem is that it opens the designated window but directly closes it (it's barely visible). Starting the program without RedirectStandardInput works. The problem is that it does not throw an exception nor any error-message. What is wrong with my code? How can I write input to the program? Thanks.

Is some.exe a console program?
You could try starting cmd.exe with the /K switch and pass your some.exe as the argument to it.