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

namespace _11012_debproject_2
{

class Program
{
    static void Main(string\[\] args);
    {
      int number1;
      int number2;
      int Multiply;

      // prompt user
      // enter first number
      Console.WriteLine( "Enter first number:" );
      number1=Convert.ToInt32(Console.Readline());
      // prompt user
      // enter second number
      Console.WriteLine( "Enter second number:");
      number2=Convert.ToIn32( Console.ReadLine());

      Multiply= number1 \* number2;

      // multiply numbers

         Console.WriteLine( "Multiply is {0}    ",Multiply);
    }
}

}

Add the following code, it should work properly I have tried it.

There are two conditions in Windows form application to open Secod Form from First form. Openning the form in Normal mode: --------------------------------- Form2 objForm2=new Form2(); objForm2.Show(); it will open the second form as normal mode. Openning the form in Model mode: --------------------------------- Form2 objForm2=new Form2(); objForm2.ShowDialog(); It will open the second form as model form.

If a .net dll is built in lower version(2.0),it can be easily used in higher version(4.0) by just referencing it. I want to explain one more thing related to that- But the the same dll is built in higher version(4.0), it can not used in Lower version(2.0) because .net does not support forward to backword compatibility that means upper to lower.