Obviously I can execute something with cmd console using Process.Start();
Is there any way to get output of that process? For example, I could have something like...
Process.Start("sample.bat");
... in my C# winforms application and sample.bat will contain something like:
echo sample loaded
First Question: is there any way to retrieve that sample loaded, after bat execution?
Second question: is there a way to use it without popped up console window?
There is an example of exactly how to do this in the Process documentation:
// Start the child process.
Process p = new Process();
// Redirect the output stream of the child process.
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.FileName = "Write500Lines.exe";
p.Start();
// Do not wait for the child process to exit before
// reading to the end of its redirected stream.
// p.WaitForExit();
// Read the output stream first and then wait.
string output = p.StandardOutput.ReadToEnd();
p.WaitForExit();
Yes, you can use
Process.Start(ProcessStartInfo)
There are a few ways to hook into I/O including ProcessStartInfo.RedirectStandardOutput available. You can use these overloads to read output from your batch files. You can also hook into the Exited event to know when execution is complete.
Use CreateNoWindow for no window.
Set process.StartInfo.RedirectStandardOutput to true and subscribe to process.OutputDataReceived
using (var process = new Process())
{
process.StartInfo = new ProcessStartInfo("exename");
process.StartInfo.RedirectStandardOutput = true;
process.OutputDataReceived += (s, ev) =>
{
string output = ev.Data;
};
process.Start();
process.BeginOutputReadLine();
process.WaitForExit();
}
Related
I tried lot's of samples posted here and elsewhere that should capture and output the StandardOutput of a process.start command. But no matter if synchronous or asynchronous the output is always empty.
StringBuilder outputBuilder;
ProcessStartInfo processStartInfo;
Process process;
outputBuilder = new StringBuilder();
processStartInfo = new ProcessStartInfo();
processStartInfo.CreateNoWindow = true;
processStartInfo.RedirectStandardOutput = true;
processStartInfo.RedirectStandardInput = true;
processStartInfo.UseShellExecute = false;
processStartInfo.Arguments = "-ss 00:00:50 -t 240 -i Input.MOV -to 00:00:02 -qscale 0 _OUTPUT.MOV";
processStartInfo.FileName = "ffmpeg.exe";
process = new Process();
process.StartInfo = processStartInfo;
// enable raising events because Process does not raise events by default
process.EnableRaisingEvents = true;
// attach the event handler for OutputDataReceived before starting the process
process.OutputDataReceived += new DataReceivedEventHandler
(
delegate(object sender, DataReceivedEventArgs e)
{
// append the new data to the data already read-in
outputBuilder.Append(e.Data);
}
);
// start the process
// then begin asynchronously reading the output
// then wait for the process to exit
// then cancel asynchronously reading the output
process.Start();
process.BeginOutputReadLine();
process.WaitForExit();
process.CancelOutputRead();
// use the output
string output = outputBuilder.ToString();
Process is executed just as intended but there is not output captured nevertheless it's shown in the VS IDE output pane.
Any idea whats going wrong here?
Best Regards.
Thanks Amy, it's correct, the normal output is returned by
BeginErrorReadLine
In C#, I am trying to run a command line program that gets input from stdin and then it returns the output to stdout . I need to keep cmd.exe running (using /k) and in a for loop, send in text and then wait for the output before sending the next text. This works if I don't redirect stdout but not after I redirect it. Initially I got data back from stdout (although much later) and now that is no longer working other than the initial call to start the program. This link says "Alternately, you can avoid the deadlock condition by creating two threads and reading the output of each stream on a separate thread."
Would that fix my issue and if so, how would I do that?
The code is set up as follows:
StringBuilde sb = new StringBuilder();
Process process = new Process();
process.StartInfo.RedirectStandardError = true;
process.StartInfo.WorkingDirectory = workingdirectory;
process.StartInfo.UseShellExecute = false;
process.StartInfo.FileName = "cmd.exe";
process.StartInfo.Arguments = "/k";
process.StartInfo.RedirectStandardOutput = true;
process.StartInfo.RedirectStandardInput = true;
process.EnableRaisingEvents = true;
process.OutputDataReceived += (sender, args) => AppendData(args.Data); //this appends the output to a stringbuilder
process.ErrorDataReceived += (sender, args) => AppendError(args.Data);
process.Start();
//sw is a streamwriter
sw= process.StandardInput;
//now call the command line code
sw.WriteLine(" some.exe some.arg ");
process.BeginOutputReadLine();
foreach(DataRow row in dtMydata.Rows)
{
mytext=row["Text"].toString();
sw.WriteLine(mytext);
sw.WriteLine(Environment.NewLine); //This redirects the text to the program,
}
I want to run an exe file by my c# code. The exe file is a console application written in c#.
The console application performs some actions which includes writing content in database and writing some files to directory.
The console application (exe file) expects some inputs from user.
Like it first asks , 'Do you want to reset database ?' y for yes and n for no.
again if user makes a choice then application again asks , 'do you want to reset files ?'
y for yes and n for no.
If user makes some choice the console application starts to get executed.
Now I want to run this exe console application by my c# code. I am trying like this
string strExePath = "exe path";
ProcessStartInfo startInfo = new ProcessStartInfo();
startInfo.CreateNoWindow = false;
startInfo.UseShellExecute = false;
startInfo.FileName = strExePath;
startInfo.WindowStyle = ProcessWindowStyle.Hidden;
using (Process exeProcess = Process.Start(startInfo))
{
exeProcess.WaitForExit();
}
I want to know how can I provide user inputs to the console application by my c# code?
Please help me out in this. Thanks in advance.
You can redirect input and output streams from your exe file.
See redirectstandardoutput
and redirectstandardinput for examples.
For reading:
// Start the child process.
Process p = new Process();
// Redirect the output stream of the child process.
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.FileName = "Write500Lines.exe";
p.Start();
// Do not wait for the child process to exit before
// reading to the end of its redirected stream.
// p.WaitForExit();
// Read the output stream first and then wait.
string output = p.StandardOutput.ReadToEnd();
p.WaitForExit();
For writing:
...
myProcess.StartInfo.RedirectStandardInput = true;
myProcess.Start();
StreamWriter myStreamWriter = myProcess.StandardInput;
myStreamWriter.WriteLine("y");
...
myStreamWriter.Close();
ProcessStartInfo has a constructor that you can pass arguments to:
public ProcessStartInfo(string fileName, string arguments);
Alternatively, you can set it on it's property:
ProcessStartInfo p = new ProcessStartInfo();
p.Arguments = "some argument";
Here is a sample of how to pass arguments to the *.exe file:
Process p = new Process();
// Redirect the error stream of the child process.
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardError = true;
p.StartInfo.FileName = #"\filepath.exe";
p.StartInfo.Arguments = "{insert arguments here}";
p.Start();
error += (p.StandardError.ReadToEnd());
p.WaitForExit();
I have a C# code that uses command prompt to call a python script. The script currently takes about 25 seconds to run. When run in command prompt, the python script has several outputs until finally outputting "done". My C# code runs the script, but never closes the command prompt if I use "WaitForExit". So my thought is I need some kind of logic to check to see if "done" has been outputted, but the internet has not been very helpful with methodology.
Here's what I have, it currently only outputs the first line, "Microsoft Windows [Version 6.1.7601]". Obviously, no good.
var p = new Process();
p.StartInfo.FileName = "cmd.exe";
p.StartInfo.WorkingDirectory = #"C:\Optimization";
p.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardInput = true;
p.Start();
p.StandardInput.WriteLine(#"ipy spot_for_labview.py");
StreamReader mySR = p.StandardOutput;
string mystr = mySR.ReadLine();
Debug.WriteLine(mystr);
p.WaitForExit(25000); //25000 is a placeholder until better method found.
p.Close();
If there's anyway to close the process after it finishes, or to get all the cmd output I'm all ears.
Any help is appreciated.
did you try this event ? Process.OutputDataReceived Event
or Process.ErrorDataReceived Event
here is the code from MSDN
Process sortProcess;
sortProcess = new Process();
sortProcess.StartInfo.FileName = "Sort.exe";
sortProcess.OutputDataReceived += new DataReceivedEventHandler(SortOutputHandler);
...
....
...
private static void SortOutputHandler(object sendingProcess,
DataReceivedEventArgs outLine)
{
}
When working with a command line program, via a c# class method.
How do you determine if the commandline program was successfully executed and the operation it has performed is ok or has failed?
Also how do you get the screen commandline output into the c# class method?
You can use the Process class to execute a command line command.
The following code captures the standard output to output, and assigns the processes exit code to exitCode.
using (Process p = new Process())
{
p.StartInfo.FileName = exeName;
p.StartInfo.Arguments = args;
p.StartInfo.UseShellExecute = false;
p.StartInfo.RedirectStandardOutput = true;
p.Start();
string output = p.StandardOutput.ReadToEnd();
p.WaitForExit();
int exitCode = p.ExitCode;
}
Something like:
Process mycommand = new Process();
mycommand.StartInfo.FileName = "myexe.exe";
mycommand.StartInfo.Arguments = "param1";
mycommand.StartInfo.UseShellExecute = false;
mycommand.StartInfo.RedirectStandardOutput = true;
mycommand.Start();
Console.WriteLine(mycommand.StandardOutput.ReadToEnd());
mycommand.WaitForExit();
You usually determine an exe's state wether the exit code is 0, but that is arguably down to the writer of the exe
I assume you're using the Process class to call the command line app.
You can find the exit code of the process using Process.ExitCode. You can redirect its standard output by setting ProcessStartInfo.RedirectStandardOutput before starting it, and then either using Process.StandardOutput or the Process.OutputDataReceived event.
Take a look at this questionenter link description here.
The additional information you might need is process.ExitCode to see if it was sucessful. Of course, the Main method of the console app must return an exit code when it is unsuccessful, which many do not.
For this, you use the Process.Start method. You can control how the process runs with the passed in ProcessStartInfo:
var myProcess = Process.Start(new ProcessStartInfo {
FileName = "process.exe",
UseShellExecute = false,
RedirectStandardOutput = true,
CreateNoWindow = true
});
if (!myProcess.WaitForExit(5000)) { // give it 5 seconds to exit
myProcess.Kill();
}
if (myProcess.ExitCode != 0) {
// error!
}
var output = myProcess.StandardOutput.ReadToEnd(); // access output