How to: Implement a Windows Communication Foundation Service Contract

This is the second of six tasks required to create a basic Windows Communication Foundation (WCF) service and a client that can call the service. For an overview of all six tasks, see the Getting Started Tutorial topic.

The next step in creating a WCF application is to implement the service interface. This involves creating a class called CalculatorService that implements the user-defined ICalculator interface..

To implement a WCF service contract

• Open the Service1.cs or Service1.vb file and add the following code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.Serialization;
using System.ServiceModel;
using System.Text;

namespace GettingStartedLib
{

    public class CalculatorService : ICalculator
    {
        public double Add(double n1, double n2)
        {
            double result = n1 + n2;
            Console.WriteLine("Received Add({0},{1})", n1, n2);
            // Code added to write output to the console window.
            Console.WriteLine("Return: {0}", result);
            return result;
        }

        public double Subtract(double n1, double n2)
        {
            double result = n1 - n2;
            Console.WriteLine("Received Subtract({0},{1})", n1, n2);
            Console.WriteLine("Return: {0}", result);
            return result;
        }

        public double Multiply(double n1, double n2)
        {
            double result = n1 * n2;
            Console.WriteLine("Received Multiply({0},{1})", n1, n2);
            Console.WriteLine("Return: {0}", result);
            return result;
        }

        public double Divide(double n1, double n2)
        {
            double result = n1 / n2;
            Console.WriteLine("Received Divide({0},{1})", n1, n2);
            Console.WriteLine("Return: {0}", result);
            return result;
        }
    }
}

Each method implements the calculator operation and writes some text to the console to make testing easier.