View Output in a Batch (.bat) file from C# code

Question

I have an c# code to execute the batch file. I want to show the information in the bat file in the command prompt. Here is my new edited c# code:

namespace CheckTime
{
class Program
{
    static void Main(string[] args)
    {
        Program Obj = new Program();

        int greetingId;
        int hourNow = System.DateTime.Now.Hour;

        if (hourNow < 12)
            greetingId = 0;
        else if (hourNow < 18)
            greetingId = 1;
        else
            greetingId = 2;
        System.Environment.ExitCode = greetingId;
        Obj.StartBatchFile(greetingId);


    }

   void StartBatchFile(int Gretting)
    {
        var p = new Process();
        p.StartInfo.FileName = "cmd.exe";
        p.StartInfo.Arguments = string.Format(@"/C D:\Nimit Joshi\Visual Studio 2013\CheckTime\CheckTime\Demo1.bat {0}", Gretting);            
        p.OutputDataReceived += ConsumeData;


        try
        {
            p.Start();
            p.WaitForExit();
        }
        finally
        {
            p.OutputDataReceived -= ConsumeData;
        }
    }

    private void ConsumeData(object sender, DataReceivedEventArgs e)
    {
        Console.WriteLine(e.Data);
    }

 }

}

Following is my Demo1.bat file:

@echo off
:: Use %1 to get the first command line parameter
goto Greeting%1%

:Greeting
echo You have no entered a greeting.
goto end

:Greeting0
echo Good Morning
goto end

:Greeting1
echo Good Afternoon
goto end

:Greeting2
echo Good Evening
goto end

:end

It is always showing You have no entered a greeting

Answer 1

Use the Process.OutputStream or listen to the Process.OutputDataReceived event.

Example:

private void ConsumeData(object sendingProcess, 
            DataReceivedEventArgs outLine)
{
    if(!string.IsNullOrWhiteSpace(outLine.Data))
        Console.WriteLine(outLine.Data);
}

p.StartInfo.RedirectStandardOutput = true;
p.StartInfo.UseShellExecute = false;
p.StartInfo.CreateNoWindow = true;
p.OutputDataReceived += ConsumeData;

try
{
    p.Start();
    p.BeginOutputReadLine();
    p.WaitForExit();
}
finally
{
    p.OutputDataReceived -= ConsumeData;
}

The batch file should be rewritten to not cause an infinite loop.

@echo off
:: Use %1 to get the first command line parameter
goto Greeting%1%

:Greeting
echo You have no entered a greeting.
goto end

:Greeting0
echo Good Morning
goto end

:Greeting1
echo Good Afternoon
goto end

:Greeting2
echo Good Evening
goto end

:end

C#

void StartBatchFile(int arg)
{
    var p = new Process();
    p.StartInfo.FileName = "cmd.exe";
    p.StartInfo.Arguments = string.Format(@"/C C:\temp\demo.bat {0}", arg);
    p.StartInfo.RedirectStandardOutput = true;
    p.StartInfo.UseShellExecute = false;
    p.StartInfo.CreateNoWindow = true;
    p.OutputDataReceived += ConsumeData;

    try
    {
        p.Start();
        p.BeginOutputReadLine();
        p.WaitForExit();
    }
    finally
    {
        p.OutputDataReceived -= ConsumeData;
    }
}

Answer 2

You return (i.e. exit your program) before you call anotherMethod().

And that's good, otherwise you'd have an infinite loop of the .exe staring the .bat.