Redirect console output to textbox in separate program

Question

This works for me:

void RunWithRedirect(string cmdPath)
{
    var proc = new Process();
    proc.StartInfo.FileName = cmdPath;

    // set up output redirection
    proc.StartInfo.RedirectStandardOutput = true;
    proc.StartInfo.RedirectStandardError = true;    
    proc.EnableRaisingEvents = true;
    proc.StartInfo.CreateNoWindow = true;
    // see below for output handler
    proc.ErrorDataReceived += proc_DataReceived;
    proc.OutputDataReceived += proc_DataReceived;

    proc.Start();

    proc.BeginErrorReadLine();
    proc.BeginOutputReadLine();

    proc.WaitForExit();
}

void proc_DataReceived(object sender, DataReceivedEventArgs e)
{
    // output will be in string e.Data
}

You can use the following code

        MemoryStream mem = new MemoryStream(1000);
        StreamWriter writer = new StreamWriter(mem);
        Console.SetOut(writer);

        Assembly assembly = Assembly.LoadFrom(@"C:\ConsoleApp.exe");
        assembly.EntryPoint.Invoke(null, null);
        writer.Close();

        string s = Encoding.Default.GetString(mem.ToArray());
        mem.Close();

I've added a number of helper methods to the O2 Platform (Open Source project) which allow you easily script an interaction with another process via the console output and input (see http://code.google.com/p/o2platform/source/browse/trunk/O2_Scripts/APIs/Windows/CmdExe/CmdExeAPI.cs)

Also useful for you might be the API that allows the viewing of the console output of the current process (in an existing control or popup window). See this blog post for more details: http://o2platform.wordpress.com/2011/11/26/api_consoleout-cs-inprocess-capture-of-the-console-output/ (this blog also contains details of how to consume the console output of new processes)