Catching runtime exceptions and outputs from python script in c# -

i'm writing wcf service runs python scripts.

for i've been using following code:

processstartinfo start = new proccessstartinfo(); start.filename = "my/full/path/to/python.exe"; start.arguments = string.format("{0} {1}", script, args); start.useshellexecute = false; start.createnowindow = true; start.redirectstandardoutput = true; start.redirectstandarderror = true;  process p = new process(); p.startinfo = start; p.start(); p.waitforexit(); string stderr = process.standarderror.readtoend(); string stdout = process.standardoutput.readtoend(); 

now i've noticed (after lot of testing) process object gets standard error/output or catches exception if error related "compilation" errors, if have undeclared variable used or stuff that, runtime exceptions , prints not being caught or able read in c# scope.

i've tried run either whole "python.exe pythoncommand.py args" sent c# code or send in processstartinfo.arguments in command line prompt , returned exceptions , prints in both cases, still when run via c# process object no exceptions thrown @ me catch , no output or error ever.

i've found nothing makes me feel kind of stupid (hopefully , has simple solution), , appreciate if has stumbled upon case me out.

thanks, matt

well, answer comment here:

but problem both exception not being thrown the python nor output read. standard output of process (and standard error well) empty – matt star

you capturing output wrong. allow capture output , should show exceptions thrown.

using system; using system.diagnostics;

namespace interactwithconsoleapp {     class program     {         static void main(string[] args)         {             processstartinfo cmdstartinfo = new processstartinfo();             cmdstartinfo.filename = @"c:\windows\system32\cmd.exe";             cmdstartinfo.redirectstandardoutput = true;             cmdstartinfo.redirectstandarderror = true;             cmdstartinfo.redirectstandardinput = true;             cmdstartinfo.useshellexecute = false;             cmdstartinfo.createnowindow = true;              process cmdprocess = new process();             cmdprocess.startinfo = cmdstartinfo;             cmdprocess.errordatareceived += cmd_error;             cmdprocess.outputdatareceived += cmd_datareceived;             cmdprocess.enableraisingevents = true;             cmdprocess.start();             cmdprocess.beginoutputreadline();             cmdprocess.beginerrorreadline();              cmdprocess.standardinput.writeline("ping www.bing.com");     //execute ping bing.com             cmdprocess.standardinput.writeline("exit");                  //execute exit.              cmdprocess.waitforexit();         }          static void cmd_datareceived(object sender, datareceivedeventargs e)         {             console.writeline("output other process");             console.writeline(e.data);         }          static void cmd_error(object sender, datareceivedeventargs e)         {             console.writeline("error other process");             console.writeline(e.data);         }     } } 

i copied code post: how parse command line output c#? have used method many times , works perfect. hope helps.