I agree that one of the downfalls of the current .NET Web service implementation is that it kind of shoe horns you into using the DOM to deal with XML when you might prefer to use an XmlReader/Writer or some other XML api. So an advantage of passing XML as a string is that you can load the string into an XmlReader and avoid the overhead of loading up an instance of a DOM. This idea has some merit in my mind, not a ton, but some.

Read this article to know why you should never return a XML string.

Recently, Matt Powell wrote about returning XML from webservices, and I certainly agree with him that returning it as an opaque string is really bad. Later on, Matevz Gacnik suggested a couple points to consider when to choose one or the other. Matt continued his rant this time tackling at the heart of the problem: why do you need to load a full-blown DOM just to get the nice XML returned from the webservice? At this point, I felt I should kick in.

This topic came up in the win_tech_off_topic list, and it caught my attention. The concept is that specifying a date in your XML document that does not conform to ISO 8601 format cannot be validated as a date type, but rather you must contrive your own simple type. For processors that use the post-schema validation Infoset (PSVI) for strong typing, this presents some non-obvious problems.

Learn how to use .NET to create a simple XML-based message broker application.

A lot of people associate the .NET framework with XML, and for good reason. .NET uses XML behind the scenes to implement many of its development tools, such as SOAP and Web services. Beyond that, however, .NET provides a powerful set of classes for working with XML directly. Whatever you need to do with XML—sequential or random access, validation, transforms, or output—the .NET Framework provides you with tools that are not only powerful but easy to use.

Last week we learned about how to use attributes in your XML elements, but what exactly is an XML element? In a nutshell, elements are the building blocks of markup languages.

XML.com recently ran an article entitled Document-Centric .NET, that highlights the various technologies for working with XML that exist in the .NET Framework. The article provides a good high level overview of the various options you have for processing XML in the .NET Framework. The article includes an all important caveat which I wish more people knew about and which I keep wanting to write an article about but never get around to doing.

The .NET platform offers several APIs you can use to parse XML documents, including forward-only, DOM, XPath, and XML serialization APIs. Each API has a distinct set of strengths and weaknesses that you should understand before starting any project that involves XML. I'll examine the API exposed by the XPathNavigator class located within the System.Xml.XPath namespace. XPathNavigator isn't as fast as the forward-only API provided by the XmlTextReader or as full-featured as the DOM, but it can be quite useful in applications that need the ability to traverse an XML document's hierarchy along a variety of axes from descendant to child to ancestor.

This example demonstrates the basics of loading XML into a DataSet. DataSet methods such as ReadXml(), GetXml() and GetXmlSchema() are called and the output of the methods is written to an ASP.NET page. The DataSet is then bound to a DataGrid.

Over the years, many industry-standard XML schemas and dialects have been developed. These industry-specific schemas embrace the original purpose of XML and are extremely valuable in promoting and supporting B2B interaction. ASP.NET Web Services do not allow developers to directly reference external schemas from within their XML Web Services interface (the WSDL file), but this article demonstrates how to build an external schema framework as an extension to ASP.NET to enable you to reference external schemas within your XML Web Service interface.

This article describes how to leverage the built-in ASP.NET XML Server Control to easily perform XML operations within your ASP.NET Web pages.

This article discusses the Microsoft XSD Inference utility, which simplifies the task of writing XML Schema by automatically generating schemas from instance documents. The inferred schema can then be refined with related document instances so that it can be used to describe and validate a whole class of XML documents.

This article, by Scott Mitchell, examines how to use XSLT to display an XML document that contains a hierarchical structure with an arbitrary depth. For example, consider an XML document that models the folders and files in a computer's file system. There might be a element, which has zero to many elements. Each element, in turn, may have zero to many elements as well (i.e., subfolders), as well as zero to many elements. In this article we'll look at how to use XSLT to display such an XML file recursively.

In the past, maintaining the state of an object in ASP often required some very inventive and painstaking code. In the brave new world of .NET, however, Object Serialization offers us a comparatively easy way to do just that, as well as some other useful tasks.

This article illustrates a mixture of common .NET methods for formatting and presenting in a readable fashion any XML document you may encounter. The latest hype with XML Web Services and even the .NET Framework itself relies on XML as its backbone, therefore this is no light matter.

One of the most common methods of binding data to a datalist is using a datareader or dataset, in this article we cover binding to a remote XML data file.

Thom Robbins explains how DataSet object features can be combined with XML to create a new type of object called the typed DataSet, which simplifies the task of data navigation.

Learn how to customize the VBCommenter PowerToy to provide the same VS .NET XML code commenting and automated code documentation functionality afforded to C# developers.

About a year ago, I got on this ASP.NET ServerControl kick. I read the Wrox book on ASP.NET Server Controls, I literally devoured everything I could find that was written about them, I read Susan Warren's excellent tutorial. In the process, I learned a great deal about ServerControls, and wrote three or four really good ones on my own. This particular control was my effort to cure some of the obvious deficiencies in the DropDownList, while adding a few neat features that I believed would be useful. The result is my "DbListBox" control, and I present it here.