WEB SERVICES
What are Web Services?
- Web services are application components
- Web services communicate using open protocols
- Web services are self-contained and self-describing
- Web services can be discovered using UDDI
- Web services can be used by other applications
- XML is the basis for Web services
The HTTP protocol is the most used Internet protocol.
Web services platform elements:
- SOAP (Simple Object Access Protocol)
- UDDI (Universal Description, Discovery and Integration)
- WSDL (Web Services Description Language)
We will explain these topics later in the tutorial.
Web Services have Two Types of Uses
Reusable application-components.
There are things applications need very often. So why make these over and over again?
Web services can offer application-components like: currency conversion, weather reports, or even language translation as services.
Connect existing software.
Web services can help to solve the interoperability problem by giving different applications a way to link their data.
With Web services you can exchange data between different applications and different platforms.
What is SOAP?
SOAP is an XML-based protocol to let applications exchange information over HTTP.
Or more simple: SOAP is a protocol for accessing a Web Service.
- SOAP stands for Simple Object Access Protocol
- SOAP is a communication protocol
- SOAP is a format for sending messages
- SOAP is designed to communicate via Internet
- SOAP is platform independent
- SOAP is language independent
- SOAP is based on XML
- SOAP is simple and extensible
- SOAP allows you to get around firewalls
- SOAP is a W3C standard
Read more about SOAP on our Home page.
What is WSDL?
WSDL is an XML-based language for locating and describing Web services.
- WSDL stands for Web Services Description Language
- WSDL is based on XML
- WSDL is used to describe Web services
- WSDL is used to locate Web services
- WSDL is a W3C standard
Read more about WSDL on our Home page.
What is UDDI?
UDDI is a directory service where companies can register and search for Web services.
- UDDI stands for Universal Description, Discovery and Integration
- UDDI is a directory for storing information about web services
- UDDI is a directory of web service interfaces described by WSDL
- UDDI communicates via SOAP
- UDDI is built into the Microsoft .NET platform
Example : FirstService.asmx
<%@WebServicelanguage=”C#”class=”FirstService”%>
using System;
using System.Web.Services;
using System.Xml.Serialization;
[WebService(Namespace=“http://localhost/MyWebServices/”)]
publicclassFirstService : WebService
{
[WebMethod]
publicint Add(int a, int b)
{
return a + b;
}
[WebMethod]
publicint Substract(int x,int y)
{
return x-y;
}
[WebMethod]
publicString SayHello()
{
return“Hello World”;
}
}
ASP.NET Button Click EVENT
protectedvoid Button1_Click(object sender, EventArgs e)
{
FirstService mySvc = new FirstService();
Label1.Text = mySvc.Substract(Int32.Parse(TextBox1.Text), Int32.Parse(TextBox2.Text)).ToString();
}
Nice Post