Covers all the topics, but needs more Learn by Example
1. Why do you need XML web services? More applications are moving to the web. Installation and configuration tasks are reduced to zero when using XML web services. Upgrades using Web services apply changes immediately. Virtually, every computer has a web browser, so client end software is not an issue. Applications using the Internet must connect to more logic and data separate across multiple machines.
2. XML web services use XML for data representation. XML data is transport over HTTP. It is easy to flow information through the firewall. You start by making some request from some client application. This triggers a response from the server. The requesting message carries information about the parameters required by the function. The web server initiates the function and returns the XML data. Http is not a proprietary data communication protocol like DCOM.
3. You can exchange messages using XML web services via HTTP-GET and HTTP-POST.
4. You must figure out what parameters to pass to the web service and you need to know what is to be returned.
5. Universal Description, Discovery, and Integration (UDDI) provide a standard way to publish and discover information about XML.
6. Consuming XML Services: you don't have build XML web services to take advantage of what they offer. You may be only interested in consuming XML Web services. XML data is accessible through any client application.
7. The follow steps are required to consume an XML Web service: discover the XML web service, create a proxy class for the XML web service, make a reference to the proxy class, create an instance of the XML web service proxy class, and access the Webmethods in the XML Web service.
8. Public Sub Calculate_OnClick(ByVal sender As Object, ByVal e As EventArgs)
Dim oService As New cMyService
txtOutput.Text = oService.Add(txtInput1.Text, txtInput2.Text)
end sub
Public Class cMyService
Inherits System.Web.Services.WebService
Public Function Add(ByVal a As Double, ByVal b As Double)
Return (a + b)
End Function
End Class
9. To create a web service, you need to create a web service class that derives from System.web.services.webservice. As you develop more and more XML web services for consumption, you'll see their power and utility withing the programming models you work with.
10. XML web services reuse capability will make them the building block components for web applications
11. XML web services can consume functions from other XML web service machines.
12. Web services are a stateless programming model. Each time a client invokes an ASP.NET web service, a new object is instantiated to handle the request. The object is destroyed after the method is called. Maintaining state information is done through either the Session object or the Application object.
Great for developers of all levels
Any book on ASP.NET will mention Web services development, but "XML Web Services for ASP.NET" is an entire book dedicated to explaining all of the different sub-areas within the technology platform. And very well done. It's written by everyone's friend in .NET, Bill Evjen, one of the most outspoken advocates of .NET technology around.The book is outstanding and takes an in-depth look at XML Web services, and Microsoft's specific implementation of the paradigm. All of the major considerations are explained well and adequately to become productive in developing your own library of Web services, or by extending the functionality of your applications.
The book's tone is very friendly, and non-intimidating, so it's a very easy, quick read. Bill also uses lots of practical analogies to make the more complex topics relevant, so it's an added bonus that this book appeals to the beginning as well as the seasoned developer.
Bill discusses areas critical to a thorough understanding of WS technology using .NET such as SOAP, UDDI, remoting, security, authentication, performance, and client development for calling an XML Web service from an ASP.NET WebForm or Windows Form, VB 6.0 app, or an ASP 3.0 Web page. The book also features some really good appendices, especially those on .NET's Web service classes, and an XSD primer for schema development.
The book is not about ASP.NET development, and so providing the reader has some experience with building third-generation Web applications, gets right to the meaty stuff. The chapters are short and to the point, and Bill's overview of ADO.NET is one of the better ones I've read in recent times. The most outstanding thing to me is that Bill liberally uses real-world code samples, with all code presented in both Visual Basic .NET and C#. Snafus in the code are very minimal, and I know form personal experience that good ol' Bill is extremely available and answers all his e-mail...about anything.
However, the book's printed code samples (I haven't checked the downloadable source code from the publisher) tend to reflect code generated from Visual Studio .NET, which in my opinion become confusing and therefore more difficult to replicate in an IDE environment like Dreamweaver MX or ASP.NET Web Matrix or non-IDE environment like Notepad due to all of the proprietary code VS.NET generates, and in doing so, using code behind. It's been my experience that it's easier to go the other way - provide the raw code and leave it up to the developer to implement in whatever means they see fit.
Another thing I did not care for (some of you may agree, I'm assuming most may not) was the physiology of the book itself, which was beyond the author's reasonable control. The binding is very flimsy and the spine breaks without much trouble. The paper isn't very durable, and doesn't lay flat for very long. I hope Wiley Publishing take into consideration that books of this nature get used & abused for their content more than most, and consider making corrections in the book's composition to make them last longer.
But beyond this, the book is a must-have for a user group as it's cross-language, multi-developmental platform, multi-subject appeal make it applicable to many different levels of developers, and is great for team environments.
Good for 70-310 exam
I was studying for the Microsoft exam 70-310 on XML Web Services and they suggested this MS press book on web services, but the MS press book is ONLY in C# even though the exam they want you to take is for Web services in VB.NET! Had to return that book. I got this one instead. I was happy to see that this book covered XML Web services in both VB.NET and C# and I was able to use this book to study for my exam. Passed!
This is not a good choice
When I purchased this book, hope will find examples, information about Web Services to help my projects. But I only found identical MSDN information. I could not believe my eyes but several of sentences was same with MSDN. If you want to buy a Web Services book this should not be one. I have purchased several books on XML Web services and this one was the most identical (also just copy and paste) one.
Unique and Awesome Ideas
Excellent book on webservices. Chapter 23 was something I had never seen before. WSDL is used extensively in the book, and Chapter 23 shows how to build take a standard HTML page and turn it into a WSDL document. What does this get you? Now you can screen scrape HTML pages and access the data as a property of the WSDL Document. I had never seen this before. Totally cool and unique technique!!
(8 reviews)
