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Learn how to use the Report Viewer with any data source and build reports on the fly for use on the web or in Windows applications.

A Single Page Application (SPA) is a different way of building HTML 5 applications from traditional Web page development. Instead of spreading the functionality of your Web applications across a collection of separate Web pages with hyperlinks between them, you instead define a single root page that the user lands on and never leaves as long as they are working with your application. You define client-side logic that switches out the data and chunks of content within that page to allow the user to navigate from logical screen to logical screen without ever leaving the page. This means that the user never sees a full page refresh while using your application. They see portions of the screen change based on their interaction, and those changes can be done in a more fluid way with transitions to enhance the user experience. You can also support using the application while offline by storing data client-side, based on some of the newer APIs of HTML 5. Taking this approach makes an SPA feel very much like a desktop application to the end user.

This article will cover how to open a listening socket and how to pass data to the serial port after the socket has connected.

Create the SQL Data Source name Programmatically

With WebForms, each ASP.NET page's rendered output includes a <form> element that performs a postback to the same page whenever a Button control within the form is clicked, or whenever the user modifies a control whose AutoPostBack property is set to True. This model simplifies web page development, but carries with it some costs - namely, the large amount of data exchanged between the client and the server during a postback. On postback the browser sends the values of all of its form fields (including hidden ones, like view state, which may be quite large) to the server; the server then sends back the entire contents of the web page. While there are some scenarios where this amount of information needs to be exchanged, in many cases the user has performed some action that requires far less information to be exchanged. With a little bit of forethought and code we can have the browser and server exchange much less data, which leads to more responsive web pages and an improved user experience.

Over the past several weeks I've been writing an article series on accessing server-side data from client script. Rather than rely solely on forms and postbacks, many websites use JavaScript code to asynchronously communicate with the server in response to the page loading or some other user action. The server, upon receiving the JavaScript-initiated request, returns just the data needed by the browser, which the browser then seamlessly integrates into the web page. There are a variety of technologies and techniques that can be employed to provide both the needed server- and client-side functionality. Last week's article, Using WCF Services with jQuery and the ASP.NET Ajax Library, explored using the Windows Communication Foundation, or WCF, to serve data from the web server and showed how to consume such a service using both the ASP.NET Ajax Library and jQuery.

In a previous 4Guys article, Creating an Online Boggle Solver, I built an application to find all solutions in a game of Boggle. (Boggle is a word game trademarked by Parker Brothers and Hasbro that involves several players trying to find as many words as they can in a 4x4 grid of letters.) This article takes the lessons learned in Using WCF Services with jQuery and the ASP.NET Ajax Library and uses them to update the user interface for my online Boggle solver, replacing the existing WebForms-based user interface with a more modern and responsive interface. I also used jQuery Templates, a JavaScript-based templating library that is useful for displaying the results from a server-side service.

Explore ways to reduce page load time, manage state efficiently, scale back on memory use, handle resources better, and improve data access in your ASP.NET applications.

The past six articles in this series have looked at how to display a grid of data in an ASP.NET MVC application and how to implement features like sorting, paging, and filtering. In each of these past six tutorials we were responsible for generating the rendered markup for the grid. Our Views included the <table> tags, the <th> elements for the header row, and a foreach loop that emitted a series of <td> elements for each row to display in the grid. While this approach certainly works, it does lead to a bit of repetition and inflates the size of our Views.

The ASP.NET MVC framework includes an HtmlHelper class that adds support for rendering HTML elements in a View. An instance of this class is available through the Html object, and is often used in a View to create action links (Html.ActionLink), textboxes (Html.TextBoxFor), and other HTML content. Such content could certainly be created by writing the markup by hand in the View; however, the HtmlHelper makes things easier by offering methods that emit common markup patterns. You can even create your own custom HTML Helpers by adding extension methods to the HtmlHelper class.

MvcContrib is a popular, open source project that adds various functionality to the ASP.NET MVC framework. This includes a very versatile Grid HTML Helper that provides a strongly-typed way to construct a grid in your Views. Using MvcContrib's Grid HTML Helper you can ditch the <table>, <tr>, and <td> markup, and instead use syntax like Html.Grid(...). This article looks at using the MvcContrib Grid to display a grid of data in an ASP.NET MVC application. A future installment will show how to configure the MvcContrib Grid to support both sorting and paging.

I thought I'd follow up on my last technical post with a few extra details about the Marble pattern, despite the name of the article I mostly talked about the Wood pattern.  I guess perhaps this is timely because the use of Promises to represent asynchronous operations is increasingly popular,  but these notions are not really limited to context pattern, though promises do make for good examples.

So, what are the essential properties?

Wood:

objects tend to be smaller and more abundant (model the nodes not the tree) dependencies and dataflow tends to be represented on a per object basis dependencies frequently make long chains (such as a series of promises lashed to one I/O) each object is participating in its own dependency chain but it they are really all the same

Marble:

objects tend to be bigger (model the tree not the nodes) dependencies and dataflow tend to flow through these big objects, the dependencies are not dependent on the size of the problem but on the necessary transforms the dataflow that SQL uses for running a query is an example of this, complexity of plan is determined by joins/merges not by data size dependencies still can make long chains but the nature of the depenencies is expressed exactly once no matter how much data there is

Again, using promises as an example (and I am not down on promises at all, they work great, but you don't have switch to the wood pattern universally just because you have async i/o)

Wood:

create many async requests for data attach additional promises to these requests for processing end each promise chain with some operation to do whatever needs doing at the end (such as inserting stuff into a DOM)

Marble:

create many async results for data give the promises to a broker which will handle all of them (and maybe created them in the first place as needed) provide any number of handlers to the broker which will run those handlers on each datum as the promises resolve

In the marble pattern I can still write nice anonymous delegates if I choose, or I can provide a class or other handler, whatever is necessary.  However I don't create one handler instance for every datum.  I created one or more broker objects that handle the various stages of processing and coordinate some or all of the post steps. 

From a memory perspective Marble is much more economical and of course it doesn't have the terrible property that I'm making lots of long lived objects.  In the wood pattern everything ends up being long lived because everything lives at least as long as the I/O request is outstanding.

The doctor prescribes a little-known technique that—under the right circumstances—lets you automatically generate new test case data from existing test cases that yield a pass result, saving time and work.

The service that Yahoo! Finance provides to download financial data is nice, but you have to know the right tags and symbols and how to build the URL to use it. This library will undertake this annoying task for you.