Redirect Running Process Output to TextBox

Question

I am trying to Direct the output of any Process given the PID to a Textbox on my Form such as cmd.exe

I use the following code but nothing is happening:

public partial class FormMain : Form
{
    private Int32 PID = 0;
    private Process process;

    public FormMain()
    {
        InitializeComponent();
    }

    private void button1_Click(object sender, EventArgs e)
    {
        PID = Convert.ToInt32(textBox2.Text);

        process = Process.GetProcessById(PID);

        process.OutputDataReceived += process_OutputDataReceived;
    }

    void process_OutputDataReceived(object sender, DataReceivedEventArgs e)
    {
        textBox1.Text += e.Data;
    }

    private void FormMain_FormClosing(object sender, FormClosingEventArgs e)
    {
        process.OutputDataReceived -= process_OutputDataReceived;
    }
}

What am I doing wrong?

This is not possible. http://stackoverflow.com/q/4093252/34397 — SLaks, Aug 22 '13 at 18:13

score 0 · Answer 1 · answered Aug 22 '13 at 18:17

0

I think the problem with what you are trying to do is with the way you are using the event. The event only fires during async output operations.

You must set:

process.StartInfo.RedirectStandardOutput = true;

Then use async read operations which will fire the event:

process.BeginOutputReadLine();

You should read the documentation for that event:

http://msdn.microsoft.com/en-us/library/system.diagnostics.process.outputdatareceived.aspx

answered Aug 22 '13 at 18:17

Ashigore

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1

No; the problem is that he isn't starting the process. – SLaks Aug 22 '13 at 18:18
1

@SLaks From the look of it he is trying to access an already running process. Does that mean that it is indeed impossible? – Ashigore Aug 22 '13 at 18:21
AFAIK, that is impossible. – SLaks Aug 23 '13 at 00:19

Redirect Running Process Output to TextBox

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