Process.StandardOutput Freeze GUI need easy fix.

Question

0.00/5 (No votes)

See more:

I was wondering if someone can help me out with this code:

C#

Process VerifyProcces = new Process();
//get path here the verify.exe is
string path = Path.GetFullPath(".\\");
VerifyProcces.StartInfo.FileName = Path.Combine(path, "verify_chunk_transition.exe");

//VerifyProcces.StartInfo.CreateNoWindow = true;
VerifyProcces.StartInfo.UseShellExecute = false;
//VerifyProcces.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
VerifyProcces.StartInfo.RedirectStandardOutput = true;
VerifyProcces.StartInfo.RedirectStandardInput = true;

//set workderection to path were the chunks are
VerifyProcces.StartInfo.WorkingDirectory = _outputpath;
VerifyProcces.StartInfo.Arguments = ".\\\\ " + _framerate + " " + pid;
VerifyProcces.Start();

MyStreamReader msr_stdout = new MyStreamReader(VerifyProcces.StandardOutput);

Thread t_stdout = new Thread(msr_stdout.Go);

t_stdout.Start();
t_stdout.Join();

VerifyProcces.WaitForExit();
string output = msr_stdout.Text;
return output;

the problem i was walking in is that the interface is freezing, now i tried to use a backgroundworker but this won't start multiple process...

i need a simple fix for easy read this process out in a new thread witch won't crash my UI.

my thanks.

Wessel

Posted 14-May-14 1:16am

Wessel Beulink

Add a Solution

Comments

dan!sh 14-May-14 7:25am

Any specific reason you are reading output in separate thread?

Wessel Beulink 14-May-14 7:56am

No i just tried to avoid working in same thread, because this gives me the trouble in the interface

BillWoodruff 14-May-14 7:32am

Have you put break-points in the code and determined that the code runs to completion ?

Wessel Beulink 14-May-14 7:52am

yes i have, the JOIN() and WAITFOREXIT() keep my UI freezing. but it restart directly because i got arround 10 requests on this process. if i remove the join and exit, i won't get any output anymore. the last function was first:<br>
<br>
string output = verifyprocess.StandardOutput without waitforexit.<br>
this was bugging my UI to for some reason the program keeps edeting the string for each line, witch makes this thread to busy

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

*dan!sh* · Accepted Answer · 2014-05-14T01:35:00

WaitForExit method call is the one that is telling main thread to wait till the process is exited. You can remove it, if possible, to keep UI thread active.

Asynchronously reading output:

C#

        private void button1_Click(object sender, EventArgs e)
        {

            using (Process process = new Process())
            {
                process.StartInfo.FileName = "Executable Location Here";
                process.StartInfo.UseShellExecute = false;
                process.StartInfo.RedirectStandardOutput = true;
                process.StartInfo.RedirectStandardError = true;
                process.StartInfo.RedirectStandardInput = true;
                process.EnableRaisingEvents = true;

                process.Exited += process_Exited;
                process.OutputDataReceived += ProccesOutputDataReceived;
                process.ErrorDataReceived += ProccesErrorDataReceived;

                process.Start();

                process.BeginOutputReadLine();
                process.BeginErrorReadLine();
            }

        }

        void process_Exited(object sender, EventArgs e)
        {
            // Handle exit here
        }

        void ProccesErrorDataReceived(object sender, DataReceivedEventArgs e)
        {
            // Handle error here
        }
void ProccesOutputDataReceived(object sender, DataReceivedEventArgs e)
        {
            // Handle output here using e.Data
        }

Code above may need modifications for complex situations involving multiple threads, quick processing in called process and other overheads.