Question

Write a C# program that allows one user to play Rock-Paper-Scissors with computer.

The user will pick a move (Rock Paper Scissors) from 3 radio buttons and click the play button to play the game. The application will use random number generator to pick a move for the computer. Then, the application display the computer's move and also display whether you won or lost the game, or the game is tie if both moves are the same.

The application must be able to record the score for number of wins for both players. Also, when you change your move, the application must clear out the current win/lose message and the computer's move.

The following codes will create one number randomly from 1, 2 or 3 and assign it to the variable num.

int num = 0;
Random rnd = new Random();
num = rnd.Next(1, 4);

Answer 1

using System;

namespace Rextester

{

    public class Program

   {

        public int playGame(int playerChoice, int computerChoice)

        {

            int ans = -2;

            switch(playerChoice)

            {

                // if player choice is scissor

                case 0 :

                                // if computer choose Rock

                                if(computerChoice == 1)

                                    ans = 0;

                                // if computer choose Paper

                                else if(computerChoice == 2)

                                    ans = 1;

                                // if computer choose Scissor

                                else

                                    ans = -1;

                                break;

                // if player choice is Rock

                case 1 :

                                // if computer choose Paper

                                if(computerChoice == 2)

                                    ans = 0;

                                // if computer choose Scissor

                                else if(computerChoice == 0)

                                    ans = 1;

                                // if computer choose Rock

                                else

                                    ans = -1;

                                break;

                // if player choice is Paper

                case 2 :

                                // if computer choose Rock

                                if(computerChoice == 1)

                                    ans = 1;

                                // if computer choose Scissor

                                else if(computerChoice == 0)

                                    ans = 0;

                                // if computer choose Paper

                                else

                                    ans = -1;

                                break;

                //default :   // for invalid choice

                //            ans = -2;

            }

            return ans;

        }

       

        public static void Main(string[] args)

        {  

            Program ob = new Program();

       

            int i;

            // create a Rando object

            Random rand = new Random();

            int playerPoints = 0, computerPoints = 0;

            Console.WriteLine("Welcome to the rock paper scissors game!\n\n");

                // generate random number in range 0 to 2

                int computerChoice = rand.Next(0, 3);

                int playerChoice;

                // infinite loop

                while(true)

                {

                    Console.WriteLine("Enter either \"rock\", \"paper\", or \"scissors\" to compete\n");

                    String pc = Console.ReadLine();

                    if(String.Compare(pc, "scissors") == 0)

                    {

                        playerChoice = 0;

                        break;

                    }

                    else if(String.Compare(pc, "rock") == 0)

                    {

                        playerChoice = 1;

                        break;

                    }

                    else if(String.Compare(pc, "paper") == 0)

                    {

                        playerChoice = 2;

                        break;

                    }

                    else

                        Console.WriteLine("Error! Please enter a valid choice.\n\n");

                }

                Console.WriteLine("The computer picked ");

                if(computerChoice == 0)

                    Console.WriteLine("scissor\n");

                else if(computerChoice == 1)

                    Console.WriteLine("rock\n");

                else

                    Console.WriteLine("paper\n");

                int result = ob.playGame(playerChoice, computerChoice);

                if(result == 1)

                {

                    Console.WriteLine("You Won!\n");

                    playerPoints++;

                }

                else if(result == 0)

                {

                    Console.WriteLine("You Loose!\n");

                    computerPoints++;

                }

                else if(result == -1)

                    Console.WriteLine("It's a draw\n");

                else

                    Console.WriteLine("Error!!\n");

        }

    }

}

Sample Output