|By Ryan Moore||
|August 11, 2003 12:00 AM EDT||
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.
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.
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.
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.
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:
If the server receives a Web request containing AMF, it forwards this request to the Flash remoting assembly.
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"
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:
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;
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
WHERE pid=" + myFlash.Params.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:
gatewayConnnection = NetServices.createGatewayConnection();
defaultService = "netJournalFlash";
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:
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:
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:
(myCombo, result, "#title#", "#pid#");
with the line:
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:
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;
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!
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.
|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?
The Internet of Things is clearly many things: data collection and analytics, wearables, Smart Grids and Smart Cities, the Industrial Internet, and more. Cool platforms like Arduino, Raspberry Pi, Intel's Galileo and Edison, and a diverse world of sensors are making the IoT a great toy box for developers in all these areas. In this Power Panel at @ThingsExpo, moderated by Conference Chair Roger Strukhoff, panelists discussed what things are the most important, which will have the most profound effect on the world, and what should we expect to see over the next couple of years.
Nov. 24, 2015 10:30 PM EST Reads: 401
PubNub has announced the release of BLOCKS, a set of customizable microservices that give developers a simple way to add code and deploy features for realtime apps.PubNub BLOCKS executes business logic directly on the data streaming through PubNub’s network without splitting it off to an intermediary server controlled by the customer. This revolutionary approach streamlines app development, reduces endpoint-to-endpoint latency, and allows apps to better leverage the enormous scalability of PubNub’s Data Stream Network.
Nov. 24, 2015 10:00 PM EST Reads: 253
I recently attended and was a speaker at the 4th International Internet of @ThingsExpo at the Santa Clara Convention Center. I also had the opportunity to attend this event last year and I wrote a blog from that show talking about how the “Enterprise Impact of IoT” was a key theme of last year’s show. I was curious to see if the same theme would still resonate 365 days later and what, if any, changes I would see in the content presented.
Nov. 24, 2015 08:00 PM EST Reads: 337
Apps and devices shouldn't stop working when there's limited or no network connectivity. Learn how to bring data stored in a cloud database to the edge of the network (and back again) whenever an Internet connection is available. In his session at 17th Cloud Expo, Ben Perlmutter, a Sales Engineer with IBM Cloudant, demonstrated techniques for replicating cloud databases with devices in order to build offline-first mobile or Internet of Things (IoT) apps that can provide a better, faster user experience, both offline and online. The focus of this talk was on IBM Cloudant, Apache CouchDB, and ...
Nov. 24, 2015 07:30 PM EST Reads: 341
Microservices are a very exciting architectural approach that many organizations are looking to as a way to accelerate innovation. Microservices promise to allow teams to move away from monolithic "ball of mud" systems, but the reality is that, in the vast majority of organizations, different projects and technologies will continue to be developed at different speeds. How to handle the dependencies between these disparate systems with different iteration cycles? Consider the "canoncial problem" in this scenario: microservice A (releases daily) depends on a couple of additions to backend B (re...
Nov. 24, 2015 06:00 PM EST Reads: 368
With all the incredible momentum behind the Internet of Things (IoT) industry, it is easy to forget that not a single CEO wakes up and wonders if “my IoT is broken.” What they wonder is if they are making the right decisions to do all they can to increase revenue, decrease costs, and improve customer experience – effectively the same challenges they have always had in growing their business. The exciting thing about the IoT industry is now these decisions can be better, faster, and smarter. Now all corporate assets – people, objects, and spaces – can share information about themselves and thei...
Nov. 24, 2015 05:30 PM EST Reads: 141
Two weeks ago (November 3-5), I attended the Cloud Expo Silicon Valley as a speaker, where I presented on the security and privacy due diligence requirements for cloud solutions. Cloud security is a topical issue for every CIO, CISO, and technology buyer. Decision-makers are always looking for insights on how to mitigate the security risks of implementing and using cloud solutions. Based on the presentation topics covered at the conference, as well as the general discussions heard between sessions, I wanted to share some of my observations on emerging trends. As cyber security serves as a fou...
Nov. 24, 2015 04:30 PM EST Reads: 285
Discussions of cloud computing have evolved in recent years from a focus on specific types of cloud, to a world of hybrid cloud, and to a world dominated by the APIs that make today's multi-cloud environments and hybrid clouds possible. In this Power Panel at 17th Cloud Expo, moderated by Conference Chair Roger Strukhoff, panelists addressed the importance of customers being able to use the specific technologies they need, through environments and ecosystems that expose their APIs to make true change and transformation possible.
Nov. 24, 2015 03:30 PM EST Reads: 459
There are over 120 breakout sessions in all, with Keynotes, General Sessions, and Power Panels adding to three days of incredibly rich presentations and content. Join @ThingsExpo conference chair Roger Strukhoff (@IoT2040), June 7-9, 2016 in New York City, for three days of intense 'Internet of Things' discussion and focus, including Big Data's indespensable role in IoT, Smart Grids and Industrial Internet of Things, Wearables and Consumer IoT, as well as (new) IoT's use in Vertical Markets.
Nov. 24, 2015 03:30 PM EST Reads: 507
Container technology is shaping the future of DevOps and it’s also changing the way organizations think about application development. With the rise of mobile applications in the enterprise, businesses are abandoning year-long development cycles and embracing technologies that enable rapid development and continuous deployment of apps. In his session at DevOps Summit, Kurt Collins, Developer Evangelist at Built.io, examined how Docker has evolved into a highly effective tool for application delivery by allowing increasingly popular Mobile Backend-as-a-Service (mBaaS) platforms to quickly crea...
Nov. 24, 2015 03:00 PM EST Reads: 284
The Internet of Things (IoT) is growing rapidly by extending current technologies, products and networks. By 2020, Cisco estimates there will be 50 billion connected devices. Gartner has forecast revenues of over $300 billion, just to IoT suppliers. Now is the time to figure out how you’ll make money – not just create innovative products. With hundreds of new products and companies jumping into the IoT fray every month, there’s no shortage of innovation. Despite this, McKinsey/VisionMobile data shows "less than 10 percent of IoT developers are making enough to support a reasonably sized team....
Nov. 24, 2015 02:00 PM EST Reads: 416
The cloud. Like a comic book superhero, there seems to be no problem it can’t fix or cost it can’t slash. Yet making the transition is not always easy and production environments are still largely on premise. Taking some practical and sensible steps to reduce risk can also help provide a basis for a successful cloud transition. A plethora of surveys from the likes of IDG and Gartner show that more than 70 percent of enterprises have deployed at least one or more cloud application or workload. Yet a closer inspection at the data reveals less than half of these cloud projects involve production...
Nov. 24, 2015 01:45 PM EST Reads: 407
As organizations realize the scope of the Internet of Things, gaining key insights from Big Data, through the use of advanced analytics, becomes crucial. However, IoT also creates the need for petabyte scale storage of data from millions of devices. A new type of Storage is required which seamlessly integrates robust data analytics with massive scale. These storage systems will act as “smart systems” provide in-place analytics that speed discovery and enable businesses to quickly derive meaningful and actionable insights. In his session at @ThingsExpo, Paul Turner, Chief Marketing Officer at...
Nov. 24, 2015 01:45 PM EST Reads: 337
Internet of @ThingsExpo, taking place June 7-9, 2016 at Javits Center, New York City and Nov 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with the 18th International @CloudExpo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world and ThingsExpo New York Call for Papers is now open.
Nov. 24, 2015 01:30 PM EST Reads: 487
We all know that data growth is exploding and storage budgets are shrinking. Instead of showing you charts on about how much data there is, in his General Session at 17th Cloud Expo, Scott Cleland, Senior Director of Product Marketing at HGST, showed how to capture all of your data in one place. After you have your data under control, you can then analyze it in one place, saving time and resources.
Nov. 24, 2015 01:30 PM EST
With major technology companies and startups seriously embracing IoT strategies, now is the perfect time to attend @ThingsExpo 2016 in New York and Silicon Valley. Learn what is going on, contribute to the discussions, and ensure that your enterprise is as "IoT-Ready" as it can be! Internet of @ThingsExpo, taking place Nov 3-5, 2015, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with 17th Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world. The Internet of Things (IoT) is the most profound cha...
Nov. 24, 2015 01:30 PM EST Reads: 480
We are rapidly moving to a brave new world of interconnected smart homes, cars, offices and factories known as the Internet of Things (IoT). Sensors and monitoring devices will touch every part of our lives. Let's take a closer look at the Internet of Things. The Internet of Things is a worldwide network of objects and devices connected to the Internet. They are electronics, sensors, software and more. These objects connect to the Internet and can be controlled remotely via apps and programs. Because they can be accessed via the Internet, these devices create a tremendous opportunity to inte...
Nov. 24, 2015 01:15 PM EST Reads: 478
Growth hacking is common for startups to make unheard-of progress in building their business. Career Hacks can help Geek Girls and those who support them (yes, that's you too, Dad!) to excel in this typically male-dominated world. Get ready to learn the facts: Is there a bias against women in the tech / developer communities? Why are women 50% of the workforce, but hold only 24% of the STEM or IT positions? Some beginnings of what to do about it! In her Day 2 Keynote at 17th Cloud Expo, Sandy Carter, IBM General Manager Cloud Ecosystem and Developers, and a Social Business Evangelist, wil...
Nov. 24, 2015 01:00 PM EST Reads: 492
Cloud computing delivers on-demand resources that provide businesses with flexibility and cost-savings. The challenge in moving workloads to the cloud has been the cost and complexity of ensuring the initial and ongoing security and regulatory (PCI, HIPAA, FFIEC) compliance across private and public clouds. Manual security compliance is slow, prone to human error, and represents over 50% of the cost of managing cloud applications. Determining how to automate cloud security compliance is critical to maintaining positive ROI. Raxak Protect is an automated security compliance SaaS platform and ma...
Nov. 24, 2015 12:00 PM EST Reads: 333
SYS-CON Events announced today that Kintone 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. kintone promotes cloud-based workgroup productivity, transparency and profitability with a seamless collaboration space, build your own business application (BYOA) platform, and workflow automation system.
Nov. 24, 2015 12:00 PM EST Reads: 565