Programming C#, Second Edition

Building a Web Service

To illustrate the techniques used to implement a web service in C# using the services classes of the .NET Framework, build a simple calculator and then make use of its functions over the Web.

Begin by specifying the web service. To do so, define a class that inherits from System.Web.Services.WebService. The easiest way to create this class is to open Visual Studio and create a new C# Web Service project. The default name that Visual Studio provides is WebService1, but you might want to choose something more appropriate.

Visual Studio .NET creates a skeleton web service and even provides a Web Service example method for you to replace with your own code, as shown in Example 16-1.

Example 16-1. Skeleton web class generated by Visual Studio .NET

using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Diagnostics;
using System.Web;
using System.Web.Services;

namespace WSCalc { /// <summary> /// Summary description for Service1. /// </summary> public class Service1 : System.Web.Services.WebService { public Service1( ) { //CODEGEN: This call is required by // the ASP.NET Web Services Designer InitializeComponent( ); } #region Component Designer generated code //Required by the Web Services Designer private IContainer components = null; /// <summary> /// Required method for Designer support - do not modify /// the contents of this method with the code editor. /// </summary> private void InitializeComponent( ) { } /// <summary> ...