How to Create Web Service Class

Web services allow desktop applications to communicate with websites.

Web services classes are created using Microsoft VB.NET or C#. The classes allow you to call a website function from a desktop application or from another website. The classes define the functions available for your users. These classes are helpful for web developers who need to make high level applications that communicate with databases online. The web service class works as a "middle-man," only allowing defined functions and procedures to interact with the database.

Instructions

1. Include the web services namespace. The .NET framework are functions available in pre-defined namespaces for web services. Insert the following code as the first line of your code:
   using System.Web.Services;

2. Define the class shell. This is the main class call that defines your class. The class shell only defines the class with no statements included. The following illustrates how to create the web service class:
   public class Util: WebService
   {
   }

3. Add a description for the class. This is shown when users browse the available functions for your web service. Below is a sample description:
   public class Util: WebService
   {
   [ WebMethod(Description="Returns the server time", EnableSession=true)]
   }

4. Create a function for your class. The functions are the elements used to perform the additions, changes or deletions from your website database. The following function is used to return the time to the user application:
   public class Util: WebService
   {
   [ WebMethod(Description="Returns the server time", EnableSession=true)]
   public string Time()
   {
   return Context.Timestamp.TimeOfDay.ToString();
   }
   }

5. Save the class and press F5 to compile and run the service. When you test a web service, a template opens with a list of open functions (in this case the "Time()" function is displayed). Click the function name and the time function executes.

References

• Microsoft: Web Services Class Examples