What are the steps to create a webservice and consume it ?

Note :- For this question this book will make a attempt by creating a simple webservice and explaining steps to acheive it. A simple webservice will be created which takes two number and gives addition result of the two number. In CD sample webservice project with folder name �MathsWebService� is provided and same will be explained below. Definitely the interviewer will not expect such a detail answer but this book will explain you in detail so that you are on right track during interview.

This webservice will add two numbers and give to the calling client.All the below steps are according to VS2005 beta editor :-
�� First create a website by clicking on File -- New WebSite.
�� From �gVisual Studio Installed Templates�h click on �gAsp.NET Web Service�h. See figure below. Name the figure as �gMaths Web Service�h.

By default the .NET editor has made a default webservice method called as "HelloWord" which returns a string datatype. Let's rename "Service.vb" to "Maths.vb" and "Service.asmx" to "Maths.asmx". Let�s replace the �HelloWorld� with following code below :-
<WebMethod()> _
Public Function AddTwoNumbers(ByVal Number1 As Integer, ByVal
Number2 As Integer) As Integer
Return Number1 + Number2
End Function


After the webservice is done click on add Webreference. Normally for components we do a �Add Reference� and for Webservices we do �Add Web Reference�.

You will be shown with a list of webservices which are known to the solutions. As we are looking for our �Maths� webservice which exist in the
same solution, we click �Webservices in this solution�.

�� Your editor has located the �gMaths�h webservice.Select the webservice.

After you have clicked on �Maths� webservice you will see a search progress bar as shown in figure below. This process will start the webservice, reference it and create a proxy for the client, so that using it client can absorb the webservice.

Finally you are able to see your webservice which is ready for use. Click on Add Reference and you will see a �Localhost� reference in your .NET solution.

We need to make a client who will absorb this �Maths Webservice�. Add �WebserviceClient.aspx� and create a UI as shown below. In the button click put in the following code. �LocalHost.ClsMaths� is the proxy object by which you can make calls to the webservice.
Sub cmdCalculate_Click(ByVal sender As Object, ByVal e As System.EventArgs) Dim pobjMaths As New localhost.ClsMaths lblResultDisplay.Text = Convert.ToString(pobjMaths.AddTwoNumbers(Convert.ToInt16(txtNumber1.Text), Convert.ToInt16(txtNumber2.Text))) End Sub