The following ASPX page implements on the client side the most simple JavaScript AJAX mechanism for both GET and POST requests, using the XML-HTTP browser-specific object. On the server side, it can respond to the AJAX requests by sending back the current date and time. Everything appears within a simple aspx file, with no code behind. The HTML shows one text entry field and two buttons: GET and POST. On any button action, an AJAX request is sent to the same page, which sends back the value entered in the text field, followed by the current server date and time, information which will be displayed below the form. The server-side script has the C# Page_Load method, which checks whether or not the page must answer to an AJAX request. The client-side script has the specific JavaScript function onSubmit, called on a button click, which issues a GET or POST AJAX request and waits for the response.

LINQ to XML is a new .NET API to transform, construct, write and read XML data, without having to resort to using additional language syntax like XPath, XSLT, DOM or SAX. LINQ to XML supports writing Query Expressions (XQuery) and can be combined with any of the other LINQ technologies. LINQ to XML types are located within the System.Xml.Linq namespace, in the .NET framework assembly with the same name. Most popular types are XDocument, XElement and XAttribute. Their constructors can take a number of optional nested arguments, to build with the same functional construction a whole hierarchy of nested XML nodes.

Web services are applications with the ability to exchange messages in a loosely coupled environment using standard protocols such as HTTP, XML, XSD, SOAP, and WSDL. XML Web services enable the building of modular applications within and across companies in heterogeneous environments making them interoperable with a broad variety of implementations, platforms and devices. The SOAP-based XML messages of these applications can have well-defined (structured and typed), or loosely defined parts (using arbitrary XML). The ability of the messages to evolve over time without breaking the protocol is fundamental to the flexibility and robustness of XML Web services as a building block for the future of the Web. The System.Web.Services namespace, from the assembly of the same name, has several classes to create such ASMX web services in ASP.NET.

Here are specific acronyms and abbreviations used in Microsoft’s .NET, with their short definitions and descriptions. Most .NET acronyms and .NET abbreviations are used for Microsoft’s .NET technologies, languages and specifications.

The System.ComponentModel.BackgroundWorker class is offered to implement the background worker pattern. With multithreading operations, you want to be able to asynchronously start a working thread and be able to cancel a long-running task, be notified when the thread completes, and provide an update on the status of the operation. The BackgroundWorker class responds to all these three events: DoWork, RunWorkerCompleted, ProgressChanged.