Imports System.Net.Dns

using System;
using System.Collections.Generic;
using System.Text;

namespace ProxyPattern
{
    class Program
    {
        static void Main(string[] args)
        {
            CalculatorProxy proxy = new CalculatorProxy();
            Console.WriteLine(
                String.Format("12 + 17 = {0}", proxy.Add(12, 17))
                );
            Console.WriteLine(
                String.Format("12 - 17 = {0}", proxy.Sub(12, 17))
                );

            Console.Read();
        }
    }

    public interface ICalculator
    {
        decimal Add(decimal x, decimal y);
        decimal Sub(decimal x, decimal y);
    }

    public class Calculator : ICalculator
    {
        public decimal Add(decimal x, decimal y)
        {
            return x + y;
        }

        public decimal Sub(decimal x, decimal y)
        {
            return x - y;
        }
    }

    public class CalculatorProxy : ICalculator
    {
        private Calculator _calculator = new Calculator();

        public decimal Add(decimal x, decimal y)
        {
            return _calculator.Add(x, y);
        }

        public decimal Sub(decimal x, decimal y)
        {
            return _calculator.Sub(x, y);
        }
    }
}

using System;
using System.Collections.Generic;
using System.Text;
using System.Security;

namespace ProxyPattern
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                CalculatorProxy proxy = new CalculatorProxy("test2");
                Console.WriteLine(
                    String.Format("12 + 17 = {0}", proxy.Add(12, 17))
                    );
                Console.WriteLine(
                    String.Format("12 - 17 = {0}", proxy.Sub(12, 17))
                    );

            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
            Console.Read();
        }
    }

    public interface ICalculator
    {
        decimal Add(decimal x, decimal y);
        decimal Sub(decimal x, decimal y);
    }

    public class Calculator : ICalculator
    {
        public decimal Add(decimal x, decimal y)
        {
            return x + y;
        }

        public decimal Sub(decimal x, decimal y)
        {
            return x - y;
        }
    }

    public class CalculatorProxy : ICalculator
    {
        private Calculator _calculator = new Calculator();
        private string _password = "test";
        private string _givenPassword = null;

        public CalculatorProxy(string password)
        {
            this._givenPassword = password;
        }

        public decimal Add(decimal x, decimal y)
        {
            if (this._givenPassword == this._password)
                return _calculator.Add(x, y);
            else
                throw new SecurityException("Not allowed: Add");
        }

        public decimal Sub(decimal x, decimal y)
        {
            if (this._givenPassword == this._password)
                return _calculator.Sub(x, y);
            else
                throw new SecurityException("Not allowed: Sub");
        }
    }
}

ProcessStartInfo psi = new ProcessStartInfo("MyPathMyApp.exe");
psi.RedirectStandardOutput = true;
psi.UseShellExecute = false;

Process p = new Process();

p.StartInfo = psi;
p.Start();
StreamReader sr = p.StandardOutput;
p.WaitForExit();
string output = sr.ReadToEnd();
sr.Close();
Debug.WriteLine(output); 

private void StartProcess()
{
    ProcessStartInfo psi = new ProcessStartInfo("MyPathMyApp.exe");
    psi.RedirectStandardOutput = true;
    psi.UseShellExecute = false;
    Process p = new Process();

    p.OutputDataReceived += 
        new DataReceivedEventHandler(p_OutputDataReceived);
    p.StartInfo = psi;
    p.Start();
    p.BeginOutputReadLine();

    p.WaitForExit();            
}

void p_OutputDataReceived(object sender, DataReceivedEventArgs e)
{
    Debug.WriteLine(e.Data);
}