.NET Process via Async/Await

process-async-await.cs

 public class Runner
    {
        public async Task<RunResults> Run(ProcessStartInfo info)
        {
            var process = new Process();
            var runResults = new RunResults();

            //some defaults that HAVE to be in place
            info.RedirectStandardOutput = true;
            info.RedirectStandardError = true;
            info.CreateNoWindow = true;
            info.UseShellExecute = false;
            process.StartInfo= info;
            process.EnableRaisingEvents = true;


            //attach to stdout
            DataReceivedEventHandler onTextIn = null;
            onTextIn = (o, a) =>
            {
                runResults.StdOut.Append(a.Data);
            };
            process.OutputDataReceived += onTextIn;


            //attach to error
            DataReceivedEventHandler onError = null;
            onError = (o, a) =>
            {

                runResults.StdOut.Append(a.Data);
            };
            process.ErrorDataReceived += onError;

            //put detachment in one place
            Action dispose = () =>
            {
                process.ErrorDataReceived -= onError;
                process.OutputDataReceived -= onTextIn;
            };


            //attach to exit
            EventHandler onExit = null;
            TaskCompletionSource<bool> tcsExit = new TaskCompletionSource<bool>();
            onExit = (o,a)=>
            {
                process.Exited-=onExit;
                process.Dispose();
                tcsExit.TrySetResult(true);
            };
            process.Exited += onExit;



            //attach to disposed
            EventHandler onDispose = null;
            TaskCompletionSource<bool> tcsDispose = new TaskCompletionSource<bool>();
            onDispose = (o,a)=>
            {
                process.Disposed-=onDispose;
                dispose();
                tcsDispose.TrySetResult(false);
            };
            process.Disposed += onDispose;
            
            //kick off the process
            process.Start();
            process.BeginOutputReadLine();
            process.BeginErrorReadLine();


            //wait for any of these to finish
            var tasks = new Task<bool>[]
            {
                tcsExit.Task,
                tcsDispose.Task
            };
            var finisher = await Task.WhenAny(tasks);
            runResults.HadError = finisher.Result;
            return runResults;
        }

    }

    public class RunResults
    {
        public bool HadError{get;set;}
        public string ResultUri{get;set;}
        public StringBuilder StdOut { get; set; }
    }