Welcome!

Microsoft Cloud Authors: Elizabeth White, Liz McMillan, Mihai Corbuleac, Pat Romanski, David Bermingham

Related Topics: Microsoft Cloud

Microsoft Cloud: Article

The Executable Internet

The Executable Internet

As the Internet evolves, the demand for a Web interface that rivals the functionality of desktop applications has become evident. The solution is the "executable Internet," a rich-client technology boasting a client-side browser plug-in capable of making the user's experience of a Web page much more interactive and powerful. The combination of ASP.NET and Macromedia's Flash Remoting is one of the most compelling rich-client interfaces available to overcome today's development limitations.

The Limitations
In order to fully leverage the immense power of the .NET Framework on the Web, an interactive, responsive, and effective desktop-like user interface is required. Limited by the restrictions of HTML and alternative technologies such as DHTML, developers are forced to conform to browser standards when building their user interface and their application's functionality. These limitations cause Web applications to be much less interactive and powerful than their desktop counterparts.

Enter the Rich Client
Rich Internet applications offer many of the same possibilities as desktop applications, with the communication power of a Web browser. Rich-client applications have the ability to immediately react to a user's input and then display, process, or validate data based on that input while the user is either on- or offline.

By executing client-side scripts, rich-client applications also make use of the processing power available on the client computer rather than relying only on the Web-hosting server. This feature allows a much more efficient use of bandwidth and processing power than strictly server-side processing.

Rich Internet applications also make the client/server communications taking place in an application nearly invisible. This is accomplished by using an asynchronous, event-driven callback model instead of the traditional Web model. This asynchronous model can also decrease the amount of Web traffic needed to communicate between client and server, and increase the interactivity of the application by allowing the client to retain control of a Web Form while a call is being made to a remote server object.

About Flash
Macromedia's Flash Player technology is the most widely distributed rich Internet application on the market today. Macromedia Flash Player is currently installed on more than 400 million client devices, including platforms such as Windows, Macintosh, Linux, Sun Solaris, Microsoft TV, Pocket PC, and others. It is estimated that a version of Flash Player is available to over 98% of Web users. Flash is supported on essentially all version 4.0+ browsers, eliminating the client interface compatibility problems encountered with other HTML-based technologies such as DHTML and Cascading Style Sheets. Because Flash is supported in both browsers and devices, Flash applications can be deployed consistently across Internet-connected platforms. Flash Player also has a vast array of multimedia capabilities, including support for motion graphics, video, audio, two-way communications, and complex forms.

Traditionally, Flash's capabilities have been utilized by developers for the familiar "skip intro" animations. With the release of Flash MX, the capabilities of Flash have changed. Flash is now an interactive medium capable of processing complex data-driven business logic as well as rich user interfaces. ActionScript, Flash's scripting language, is a powerful object-oriented scripting language based on the ECMA-262 standard, which is also followed by JavaScript and Microsoft's JScript, making programming in Flash an easy transition for .NET developers.

Flash Remoting .NET
The component essential to the success of rich-client interfaces is the ability to quickly access server-side data. Macromedia's Flash Remoting for .NET provides an interface for communicating between Flash Player and .NET application servers.

Flash Remoting exposes .NET technologies such as Web services, ASP.NET pages, and .NET assemblies as remote services to Flash, allowing them to be called as if they were local ActionScript objects. Flash Remoting MX is used in .NET applications as a custom server control in ASP.NET pages or as a namespace in .NET assemblies, code-behind class files, and Web services. This gives the .NET developer the flexibility to build server-side logic in a variety of formats, all of which are accessible to the client.

Flash Remoting provides transparent conversions between Flash data types and the server-side .NET data types. These conversions take much of the work out of the hands of both the client and server-side developers, allowing focus to reside on the business logic and client interactivity instead of the object communication.

Flash Remoting for .NET communicates between the Flash client and the .NET server using a message format called AMF (Action Message Format), which is delivered over HTTP and modeled on SOAP. AMF is a binary message format, the likes of which have been found to reduce network traffic up to 50% compared to SOAP-formatted communication. Because it is delivered over HTTP, AMF is also securable via HTTPS and is firewall safe.

The Flash Remoting .NET environment consists of two layers: (1) the netservices layer, residing in the client Flash Player (available on all Flash Players version 6.40+); and (2) the remoting gateway, residing on the .NET Web server. The netservices layer is composed of a Flash include file containing all of the ActionScript classes necessary to send and receive communications on the Flash side. The remoting gateway consists of a .NET DLL that acts as controller on the .NET runtime that, among other things, handles the conversion of data types between ActionScript and the .NET Common Language Runtime. When this controller receives a request, the request passes through a series of filters that handle serializing, logging, and security before arriving at a service adapter that handles the appropriate invocation type.

Make It Happen
In order to demonstrate how to use .NET Flash Remoting, as well as introduce some ActionScript, I have created a .NET Remoting application available for download from www.sys-con.com/dotnet/sourcec.cfm. In my example I'll demonstrate how to pass DataTables from an ASP.NET page to a Flash object and bind that data to Flash user controls. In this example, you will see how an event-driven, asynchronous model is used to retrieve data from a Web server while allowing a client to retain control of the Web page.

Setting Up
Download and install the Flash MX authoring environment 30-day trial from www.macromedia.com/software/flash, and the Flash Remoting 30-day trial from www.macromedia.com/software/flashremoting. When installed, Flash Remoting will reside in a directory under c:\inetpub\wwwroot\flashremoting (in a typical IIS install).

Next, create a directory anywhere on your system for the application files. This directory will need to be enabled for Web sharing. In my example, I have shared the folder as netJournalFlash. Create a "bin" directory with write permissions within this directory to function as the local assembly cache. Now we copy a couple of files from the flashremoting directory to the new application directory. Copy the flashremoting/bin directory and the flashgateway.dll file, which is the server-side remoting gateway, to the bin directory of the new application. Also copy the Web.config file to the directory root.

The Web.config file contains one of the essential server-side requirements for Flash Remoting, a reference to the Flash Remoting assembly:


type="FlashGateway.
Controller.Gateway
Controller,
flashgateway" />

If the server receives a Web request containing AMF, it forwards this request to the Flash remoting assembly.

.NET Programming
The ASP.NET code in this example consists of two pages, productList.aspx and productData.aspx. To access data from an ASP.NET file and pass data to and from Flash files, a Flash Remoting custom server control must be used within the page. First, register the Flash gateway:

<%@ Register TagPrefix="MM" Namespace="FlashGateway"
Assembly="flashgateway" %>

The Flash control is added to the page with the following statement:

The Flash Remoting custom server controls contain three properties used to access variables passed to and from Flash:

- Flash.Params
- Flash.Result
- Flash.DataSource

The Flash.Params property is an array of parameters passed from Flash to the .NET application. The Flash.Result property is used to return data to Flash after the server-side processing has occurred. The Flash.DataSource property is used to bind .NET DataSets to Flash Remoting controls.

Let's take a look at the example files. When productList.aspx is invoked, a connection is made to a local Access database and a DataSet is retrieved consisting of the product ID and name for each product in the database. This DataTable is then bound to the Flash control using the control's DataSource property and DataBind() method.

myFlash.DataSource = myDataSet.Tables[0];
myFlash.DataBind();

ProductData.aspx is very similar to productList.aspx, except that it requires a parameter to be passed to it from the Flash client and returns the detailed listing for that single product. In this file, we first check to make sure that a parameter has been passed through the Flash Control, then make the connection to the datasource. The SQL query is then built, using the passed parameter to determine which product to select further data for:

string sqlQuery="SELECT description, location, price
FROM productData
WHERE pid=" + myFlash.Params[0].ToString();

And the resulting DataTable is bound to the Flash control as shown in productList.aspx, one of the source files.

Time for Some Action(Script)
Now that we've constructed our server-side .NET code, it's time to tackle the front-end Flash. Flash files are constructed on a timeline consisting of a number of layers. In our file, the top layer (as seen in the "Timeline" window) is titled "functions". When the first frame of this layer is selected, the code for this frame appears in the "Actions" panel. This frame is where all of our ActionScript code will reside. More information about programming in Flash can be found at: www.macromedia.com/support/flash. As mentioned earlier, the netservices layer is the client portion of the Flash Remoting model. The netservices layer is initiated in ActionScript with the following call:

NetServices.setDefaultGatewayUrl
("http://localhost/netjournal/gateway.aspx");
gatewayConnnection = NetServices.createGatewayConnection();
defaultService = "netJournalFlash";
flashService =gatewayConnnection.
getService(defaultService,this);

The gateway.aspx file is a blank ASP.NET file used only when developing in the Flash Authoring Environment. In production, the setDefaultGatewayURL is removed, and the gateway is supplied through a parameter in the HTML that embeds the SWF file in the Web page.

Once this connection is made, the remote .NET service methods may be accessed as if they were local Flash ActionScript resources. The service function we will use will reside inside the netJournalFlash application (or whatever you named your app), so we set our default service to netJournalFlash. To make a call to an ASP.NET page containing a remoting object we would like to invoke, a call to the service function is made, with the name of the ASP.NET page being the name of the method being called:

flashService.productList();

This function calls the productList.aspx page and waits for a response. When a response is received, Flash automatically forwards this response to a function with the name of the call followed by "_Result", in this case:

function productList_Result(result)

When the result is successfully received, this data is then bound to the Flash comboBox with the instance name "myCombo" using the Flash DataGlue ActionScript object, also included with Flash Remoting:

DataGlue.bindFormatStrings
(myCombo, result, "#title#", "#pid#");

with the line:

myCombo.setChangeHandler("loadImageData");

The comboBox has been set to execute the loadImageData function when an item has been selected.

In the function loadImageData, we call the productData.aspx page, passing the value of the product we would like to retrieve the data for:

flashService.productData(myCombo.getValue());

When the response is received by the productData.aspx page, it is automatically handled by the productData_result function. In this function, we set the price and description text fields to their respective values, as well as load the image associated with this product with the line:

theImage = "images/"+result.getItemAt(0).location;
loadMovie(theImage, imgHolder);

Line one creates a string variable named "theImage" and sets it to the images directory, followed by the first result's location column. Line two then loads this image into the imgHolder movieClip on the stage, and our Flash is complete!

Conclusion
As the demand for a more and more interactive Web user experience increases, the need for rich-client interfaces has increased exponentially. As you have seen in the example, the combination of .NET objects, Macromedia Flash Remoting, and Macromedia's Flash Player create a powerful rich-client interface capable of producing desktop-like applications in a Web browser interface.

More Stories By Ryan Moore

Ryan Moore is the lead software architect and a principal of Balance Studios Inc. (www.balancestudios.com) as well as epicsoft, Inc. (www.epicsoft.net) of Green Bay, WI. Ryan is a C# programmer and Certified Macromedia Flash Developer. Ryan currently maintains a weblog at http://blogs.ittoolbox.com/c/engineering/

Comments (1) View Comments

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


Most Recent Comments
Eric Ball 03/17/05 01:30:13 PM EST

I am running thru your tutorial 'The Executable Internet'...this is what i have been looking for to shed some light on the FlashRemoting subject.

Do you have the products.mdb for download so that i can complete the tutorial and get a better understanding of how this works?

Thanks
Eric
Enviromed

@ThingsExpo Stories
The IoTs will challenge the status quo of how IT and development organizations operate. Or will it? Certainly the fog layer of IoT requires special insights about data ontology, security and transactional integrity. But the developmental challenges are the same: People, Process and Platform. In his session at @ThingsExpo, Craig Sproule, CEO of Metavine, will demonstrate how to move beyond today's coding paradigm and share the must-have mindsets for removing complexity from the development proc...
SYS-CON Events announced today that EastBanc Technologies will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. EastBanc Technologies has been working at the frontier of technology since 1999. Today, the firm provides full-lifecycle software development delivering flexible technology solutions that seamlessly integrate with existing systems – whether on premise or cloud. EastBanc Technologies partners with p...
SYS-CON Events announced today that ContentMX, the marketing technology and services company with a singular mission to increase engagement and drive more conversations for enterprise, channel and SMB technology marketers, has been named “Sponsor & Exhibitor Lounge Sponsor” of SYS-CON's 18th Cloud Expo, which will take place on June 7-9, 2016, at the Javits Center in New York City, New York. “CloudExpo is a great opportunity to start a conversation with new prospects, but what happens after the...
WebRTC is bringing significant change to the communications landscape that will bridge the worlds of web and telephony, making the Internet the new standard for communications. Cloud9 took the road less traveled and used WebRTC to create a downloadable enterprise-grade communications platform that is changing the communication dynamic in the financial sector. In his session at @ThingsExpo, Leo Papadopoulos, CTO of Cloud9, will discuss the importance of WebRTC and how it enables companies to fo...
The IoT is changing the way enterprises conduct business. In his session at @ThingsExpo, Eric Hoffman, Vice President at EastBanc Technologies, discuss how businesses can gain an edge over competitors by empowering consumers to take control through IoT. We'll cite examples such as a Washington, D.C.-based sports club that leveraged IoT and the cloud to develop a comprehensive booking system. He'll also highlight how IoT can revitalize and restore outdated business models, making them profitable...
SYS-CON Events announced today that MangoApps will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. MangoApps provides modern company intranets and team collaboration software, allowing workers to stay connected and productive from anywhere in the world and from any device. For more information, please visit https://www.mangoapps.com/.
SYS-CON Events announced today the How to Create Angular 2 Clients for the Cloud Workshop, being held June 7, 2016, in conjunction with 18th Cloud Expo | @ThingsExpo, at the Javits Center in New York, NY. Angular 2 is a complete re-write of the popular framework AngularJS. Programming in Angular 2 is greatly simplified. Now it’s a component-based well-performing framework. The immersive one-day workshop led by Yakov Fain, a Java Champion and a co-founder of the IT consultancy Farata Systems and...
What a difference a year makes. Organizations aren’t just talking about IoT possibilities, it is now baked into their core business strategy. With IoT, billions of devices generating data from different companies on different networks around the globe need to interact. From efficiency to better customer insights to completely new business models, IoT will turn traditional business models upside down. In the new customer-centric age, the key to success is delivering critical services and apps wit...
Join us at Cloud Expo | @ThingsExpo 2016 – June 7-9 at the Javits Center in New York City and November 1-3 at the Santa Clara Convention Center in Santa Clara, CA – and deliver your unique message in a way that is striking and unforgettable by taking advantage of SYS-CON's unmatched high-impact, result-driven event / media packages.
In his keynote at 18th Cloud Expo, Andrew Keys, Co-Founder of ConsenSys Enterprise, will provide an overview of the evolution of the Internet and the Database and the future of their combination – the Blockchain. Andrew Keys is Co-Founder of ConsenSys Enterprise. He comes to ConsenSys Enterprise with capital markets, technology and entrepreneurial experience. Previously, he worked for UBS investment bank in equities analysis. Later, he was responsible for the creation and distribution of life ...
SYS-CON Events announced today that BMC Software has been named "Siver Sponsor" of SYS-CON's 18th Cloud Expo, which will take place on June 7-9, 2015 at the Javits Center in New York, New York. BMC is a global leader in innovative software solutions that help businesses transform into digital enterprises for the ultimate competitive advantage. BMC Digital Enterprise Management is a set of innovative IT solutions designed to make digital business fast, seamless, and optimized from mainframe to mo...
SYS-CON Events announced today that MobiDev will exhibit at SYS-CON's 18th International Cloud Expo®, which will take place on June 7-9, 2016, at the Javits Center in New York City, NY. MobiDev is a software company that develops and delivers turn-key mobile apps, websites, web services, and complex software systems for startups and enterprises. Since 2009 it has grown from a small group of passionate engineers and business managers to a full-scale mobile software company with over 200 develope...
As cloud and storage projections continue to rise, the number of organizations moving to the cloud is escalating and it is clear cloud storage is here to stay. However, is it secure? Data is the lifeblood for government entities, countries, cloud service providers and enterprises alike and losing or exposing that data can have disastrous results. There are new concepts for data storage on the horizon that will deliver secure solutions for storing and moving sensitive data around the world. ...
SoftLayer operates a global cloud infrastructure platform built for Internet scale. With a global footprint of data centers and network points of presence, SoftLayer provides infrastructure as a service to leading-edge customers ranging from Web startups to global enterprises. SoftLayer's modular architecture, full-featured API, and sophisticated automation provide unparalleled performance and control. Its flexible unified platform seamlessly spans physical and virtual devices linked via a world...
Companies can harness IoT and predictive analytics to sustain business continuity; predict and manage site performance during emergencies; minimize expensive reactive maintenance; and forecast equipment and maintenance budgets and expenditures. Providing cost-effective, uninterrupted service is challenging, particularly for organizations with geographically dispersed operations.
SYS-CON Events announced today TechTarget has been named “Media Sponsor” of SYS-CON's 18th International Cloud Expo, which will take place on June 7–9, 2016, at the Javits Center in New York City, NY, and the 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. TechTarget is the Web’s leading destination for serious technology buyers researching and making enterprise technology decisions. Its extensive global networ...
SYS-CON Events announced today that Commvault, a global leader in enterprise data protection and information management, has been named “Bronze Sponsor” of SYS-CON's 18th International Cloud Expo, which will take place on June 7–9, 2016, at the Javits Center in New York City, NY, and the 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Commvault is a leading provider of data protection and information management...
The essence of data analysis involves setting up data pipelines that consist of several operations that are chained together – starting from data collection, data quality checks, data integration, data analysis and data visualization (including the setting up of interaction paths in that visualization). In our opinion, the challenges stem from the technology diversity at each stage of the data pipeline as well as the lack of process around the analysis.
A strange thing is happening along the way to the Internet of Things, namely far too many devices to work with and manage. It has become clear that we'll need much higher efficiency user experiences that can allow us to more easily and scalably work with the thousands of devices that will soon be in each of our lives. Enter the conversational interface revolution, combining bots we can literally talk with, gesture to, and even direct with our thoughts, with embedded artificial intelligence, wh...
Designing IoT applications is complex, but deploying them in a scalable fashion is even more complex. A scalable, API first IaaS cloud is a good start, but in order to understand the various components specific to deploying IoT applications, one needs to understand the architecture of these applications and figure out how to scale these components independently. In his session at @ThingsExpo, Nara Rajagopalan is CEO of Accelerite, will discuss the fundamental architecture of IoT applications, ...