Reading/Writing to a command line program in c#

Question

I\'m trying to talk to a command-line program from C#. It is a sentiment analyser. It works like this:

CMD> java -jar analyser.jar

>

Answer 1

This is not a general question, but rather a application-specific one. I just happened to be working on the same thing. We probably should not discuss about this here, but forgive me I just want to help.

The key point is that you need to enter the right arguments for the jar

var processInfo = new ProcessStartInfo("java.exe", "-jar SentiStrengthCom.jar stdin sentidata data201109/ scale"){ ... }

Below is a working solution:

    // Start the java server, probably in a background thread
    void bgw_DoWork(object sender, DoWorkEventArgs e)
    {
        string directory = ...; // the directory of jar

        var processInfo = new ProcessStartInfo("java.exe", "-jar SentiStrengthCom.jar stdin sentidata data201109/ scale")
        {
            // Initialize properties of "processInfo"
            CreateNoWindow = true,
            UseShellExecute = false, 
            WorkingDirectory = directory,
            RedirectStandardOutput = true,
            RedirectStandardError = true,
            RedirectStandardInput = true,
        };

        JavaSentiStrength = new Process();
        JavaSentiStrength.StartInfo = processInfo;

        JavaSentiStrength.Start();

        Console.WriteLine("SentiStrengthCom Java is running...");

        JavaSentiStrength.WaitForExit();

        int exitCode = 0;
        if (JavaSentiStrength != null) exitCode = JavaSentiStrength.ExitCode;
        Debug.WriteLine("Java SentiStrengthCom closed down! " + exitCode);
        JavaSentiStrength.Close();
        JavaSentiStrength = null;

    }

    // A button click
    private void btnRequest_Click(object sender, EventArgs e)
    {
        JavaSentiStrength.StandardInput.WriteLine("love you ");
        string s_out = JavaSentiStrength.StandardOutput.ReadLine();
        Debug.WriteLine("SentiStrengthCom output: " + s_out);
    }

The output is

SentiStrengthCom output: 3 -1 2

Hope it helps!