|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?
In the next forty months – just over three years – businesses will undergo extraordinary changes. The exponential growth of digitization and machine learning will see a step function change in how businesses create value, satisfy customers, and outperform their competition. In the next forty months companies will take the actions that will see them get to the next level of the game called Capitalism. Or they won’t – game over. The winners of today and tomorrow think differently, follow different...
Oct. 22, 2016 04:30 AM EDT Reads: 790
One of biggest questions about Big Data is “How do we harness all that information for business use quickly and effectively?” Geographic Information Systems (GIS) or spatial technology is about more than making maps, but adding critical context and meaning to data of all types, coming from all different channels – even sensors. In his session at @ThingsExpo, William (Bill) Meehan, director of utility solutions for Esri, will take a closer look at the current state of spatial technology and ar...
Oct. 22, 2016 03:30 AM EDT Reads: 1,661
The Open Connectivity Foundation (OCF), sponsor of the IoTivity open source project, and AllSeen Alliance, which provides the AllJoyn® open source IoT framework, today announced that the two organizations’ boards have approved a merger under the OCF name and bylaws. This merger will advance interoperability between connected devices from both groups, enabling the full operating potential of IoT and representing a significant step towards a connected ecosystem.
Oct. 22, 2016 02:45 AM EDT Reads: 1,145
SYS-CON Media announced today that @WebRTCSummit Blog, the largest WebRTC resource in the world, has been launched. @WebRTCSummit Blog offers top articles, news stories, and blog posts from the world's well-known experts and guarantees better exposure for its authors than any other publication. @WebRTCSummit Blog can be bookmarked ▸ Here @WebRTCSummit conference site can be bookmarked ▸ Here
Oct. 22, 2016 01:30 AM EDT Reads: 9,608
SYS-CON Events announced today that Streamlyzer will exhibit at the 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Streamlyzer is a powerful analytics for video streaming service that enables video streaming providers to monitor and analyze QoE (Quality-of-Experience) from end-user devices in real time.
Oct. 22, 2016 01:15 AM EDT Reads: 889
You have great SaaS business app ideas. You want to turn your idea quickly into a functional and engaging proof of concept. You need to be able to modify it to meet customers' needs, and you need to deliver a complete and secure SaaS application. How could you achieve all the above and yet avoid unforeseen IT requirements that add unnecessary cost and complexity? You also want your app to be responsive in any device at any time. In his session at 19th Cloud Expo, Mark Allen, General Manager of...
Oct. 22, 2016 01:15 AM EDT Reads: 806
@ThingsExpo has been named the Top 5 Most Influential Internet of Things Brand by Onalytica in the ‘The Internet of Things Landscape 2015: Top 100 Individuals and Brands.' Onalytica analyzed Twitter conversations around the #IoT debate to uncover the most influential brands and individuals driving the conversation. Onalytica captured data from 56,224 users. The PageRank based methodology they use to extract influencers on a particular topic (tweets mentioning #InternetofThings or #IoT in this ...
Oct. 22, 2016 01:00 AM EDT Reads: 8,146
SYS-CON Events announced today that Super Micro Computer, Inc., a global leader in Embedded and IoT solutions, will exhibit at SYS-CON's 20th International Cloud Expo®, which will take place on June 7-9, 2017, at the Javits Center in New York City, NY. Supermicro (NASDAQ: SMCI), the leading innovator in high-performance, high-efficiency server technology, is a premier provider of advanced server Building Block Solutions® for Data Center, Cloud Computing, Enterprise IT, Hadoop/Big Data, HPC and ...
Oct. 22, 2016 12:30 AM EDT Reads: 3,490
Cloud based infrastructure deployment is becoming more and more appealing to customers, from Fortune 500 companies to SMEs due to its pay-as-you-go model. Enterprise storage vendors are able to reach out to these customers by integrating in cloud based deployments; this needs adaptability and interoperability of the products confirming to cloud standards such as OpenStack, CloudStack, or Azure. As compared to off the shelf commodity storage, enterprise storages by its reliability, high-availabil...
Oct. 22, 2016 12:15 AM EDT Reads: 965
Explosive growth in connected devices. Enormous amounts of data for collection and analysis. Critical use of data for split-second decision making and actionable information. All three are factors in making the Internet of Things a reality. Yet, any one factor would have an IT organization pondering its infrastructure strategy. How should your organization enhance its IT framework to enable an Internet of Things implementation? In his session at @ThingsExpo, James Kirkland, Red Hat's Chief Arch...
Oct. 22, 2016 12:00 AM EDT Reads: 5,934
The IoT industry is now at a crossroads, between the fast-paced innovation of technologies and the pending mass adoption by global enterprises. The complexity of combining rapidly evolving technologies and the need to establish practices for market acceleration pose a strong challenge to global enterprises as well as IoT vendors. In his session at @ThingsExpo, Clark Smith, senior product manager for Numerex, will discuss how Numerex, as an experienced, established IoT provider, has embraced a ...
Oct. 22, 2016 12:00 AM EDT Reads: 939
SYS-CON Events announced today that Cloudbric, a leading website security provider, will exhibit at the 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Cloudbric is an elite full service website protection solution specifically designed for IT novices, entrepreneurs, and small and medium businesses. First launched in 2015, Cloudbric is based on the enterprise level Web Application Firewall by Penta Security Sys...
Oct. 21, 2016 11:45 PM EDT Reads: 989
We are reaching the end of the beginning with WebRTC, and real systems using this technology have begun to appear. One challenge that faces every WebRTC deployment (in some form or another) is identity management. For example, if you have an existing service – possibly built on a variety of different PaaS/SaaS offerings – and you want to add real-time communications you are faced with a challenge relating to user management, authentication, authorization, and validation. Service providers will w...
Oct. 21, 2016 11:45 PM EDT Reads: 3,217
When people aren’t talking about VMs and containers, they’re talking about serverless architecture. Serverless is about no maintenance. It means you are not worried about low-level infrastructural and operational details. An event-driven serverless platform is a great use case for IoT. In his session at @ThingsExpo, Animesh Singh, an STSM and Lead for IBM Cloud Platform and Infrastructure, will detail how to build a distributed serverless, polyglot, microservices framework using open source tec...
Oct. 21, 2016 11:45 PM EDT Reads: 4,417
November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Penta Security is a leading vendor for data security solutions, including its encryption solution, D’Amo. By using FPE technology, D’Amo allows for the implementation of encryption technology to sensitive data fields without modification to schema in the database environment. With businesses having their data become increasingly more complicated in their mission-critical applications (such as ERP, CRM, HRM), continued ...
Oct. 21, 2016 11:45 PM EDT Reads: 873
You think you know what’s in your data. But do you? Most organizations are now aware of the business intelligence represented by their data. Data science stands to take this to a level you never thought of – literally. The techniques of data science, when used with the capabilities of Big Data technologies, can make connections you had not yet imagined, helping you discover new insights and ask new questions of your data. In his session at @ThingsExpo, Sarbjit Sarkaria, data science team lead ...
Oct. 21, 2016 10:00 PM EDT Reads: 4,220
A completely new computing platform is on the horizon. They’re called Microservers by some, ARM Servers by others, and sometimes even ARM-based Servers. No matter what you call them, Microservers will have a huge impact on the data center and on server computing in general. Although few people are familiar with Microservers today, their impact will be felt very soon. This is a new category of computing platform that is available today and is predicted to have triple-digit growth rates for some ...
Oct. 21, 2016 10:00 PM EDT Reads: 33,899
SYS-CON Events announced today that Roundee / LinearHub will exhibit at the WebRTC Summit at @ThingsExpo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. LinearHub provides Roundee Service, a smart platform for enterprise video conferencing with enhanced features such as automatic recording and transcription service. Slack users can integrate Roundee to their team via Slack’s App Directory, and '/roundee' command lets your video conference ...
Oct. 21, 2016 09:15 PM EDT Reads: 1,984
SYS-CON Events announced today that Enzu will exhibit at the 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Enzu’s mission is to be the leading provider of enterprise cloud solutions worldwide. Enzu enables online businesses to use its IT infrastructure to their competitive advantage. By offering a suite of proven hosting and management services, Enzu wants companies to focus on the core of their online busine...
Oct. 21, 2016 09:15 PM EDT Reads: 1,204
SYS-CON Events announced today that SoftNet Solutions will exhibit at the 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. SoftNet Solutions specializes in Enterprise Solutions for Hadoop and Big Data. It offers customers the most open, robust, and value-conscious portfolio of solutions, services, and tools for the shortest route to success with Big Data. The unique differentiator is the ability to architect and...
Oct. 21, 2016 08:15 PM EDT Reads: 373