Welcome!

IoT User Interface Authors: Elizabeth White, John Basso, Liz McMillan, Shelly Palmer, AppDynamics Blog

Related Topics: IoT User Interface, Microsoft Cloud

IoT User Interface: Article

Google Maps! AJAX-Style Web Development Using ASP.NET

Taking asynchronous Web forms to the next level

In the past few months, the design pattern of combining Asynchronous JavaScript and XML (AJAX) to develop highly interactive Web applications has been growing in popularity. High-profile Web applications such as Google Maps and A9 are currently leveraging the combination of these technologies to produce rich client-side user experiences. The individual technologies that compose AJAX are not recent developments; they have been around for some time and have been continuously updated and improved. However, it is the recent confluence of these technologies that is leading to interesting possibilities.

I have three goals in this article. First, I want to provide a high-level overview of AJAX-style applications. My second goal is to provide a detailed description of asynchronous callback features of ASP.NET 2.0. Finally, I want to provide an insight into upcoming enhancements of tools and frameworks for building AJAX-style applications.

AJAX-style Web applications exhibit the following characteristics:

  • Asynchronous requests made to the Web server. The browser user interface is not blocked while waiting for a response from the Web server. The browser can continue to respond to user interaction while awaiting a server response.
  • High dependence on browser-based logic written in JavaScript. Recent enhancements to and standardization of the W3C DOM provide support for dynamic client-side updates to UI.
  • Exchange of nonpresentation XML-based data between the browser and the Web server. The XMLHttp object makes it possible to communicate with the Web server without the need to reload the page.
The big difference between an AJAX application and a traditional Web application is that every user interaction does not result in an HTTP request being sent to the Web server. Instead, browser-based logic implemented in JavaScript receives control that, in turn, decides whether to handle the request locally or to make an asynchronous call to the server. Upon the completion of the asynchronous call to the server, the client-side logic appropriately updates the relevant sections of the UI. This approach provides the following benefits:
  • The user experience is richer. For example, when a Google map user drags the map in one direction, an asynchronous request is made to the server in the background, to continue to fetch tiles beyond the edge of the screen. This way when the user drags the map further, the new image is readily available. This creates a perception of a speedier response.
  • Since the state is not lost across XMLHttp-based calls to the server, AJAX applications can avoid rerendering the UI widgets each time.
  • More logic residing in the browser reduces the number of roundtrips to the Web server, thereby improving the overall latency of the system.
For all the pros, AJAX-style applications have a number of cons associated with them as well. AJAX-style development is difficult because of the absence of framework (a collection of UI classes similar to the MFC toolkit for Windows) and IDE support (i.e., debugging, visual designers, etc.). One has to know at least two languages well (DHTML and JavaScript). Further, AJAX-style applications take longer to code because of the additional testing required to support multiple browser versions and types. Finally, as the JavaScript-based source is accessible to the end user, threat analysis becomes very important.

Fortunately, the arrival of things such as Atlas, AJAX.NET, and the Google Maps API etc. is a sign of better support for building AJAX-style applications in the future. In the next section, we will look into how the support for building AJAX applications is evolving over time and what to expect from the newly announced toolkits such as Atlas.

Let's start with the XMLHttp object, which was introduced by Microsoft and later implemented on other platforms including Mozilla and Apple's Safari browser. XMLHttp enables asynchronous requests to the Web server, which allows Javascript- based logic on the client to call the Web server without the need to reload the page.

In other words, it is possible to have interaction with the Web server in the background without causing a page reload - a side effect of the exchange between the browser and the Web server.

Using the XMLHttp object is straightforward. For the sake of simplicity, let's just consider IE specific syntax. The syntax for XMLHttp implementations on other browsers is similar.


request = new ActiveXObject("Microsoft.XMLHTTP");
if (request)
{
request.onreadystatechange = CallbackHandler;
request.open("GET", URL, true);
request.send();
}

function CallbackHandler()
{
if ((request.readyState == 4) && (request.status == 200)
{
string response = request.responseXML;

// Update the relevant sections of the UI

}
}
In the code snippet shown above, the first step is to instantiate the Microsoft.XMLHttp class. Next, we set the properties on the XMLHttp instance we just created, including the address of callback function that will get control when the XMLHttp request is complete. The callback function address is needed because we are making asynchronous calls to the server (an intent conveyed by setting the third parameter on the open method call to true). Inside the implementation for the callback function, we make additional checks to make sure that the request is complete.

More Stories By Vishwas Lele

Vishwas Lele is a principal architect at Applied Information Sciences (www.appliedis.com), a system and software engineering company specializing in .NET-based solutions. Vishwas also serves as the MSDN Regional Director for the Washington, DC area.

Comments (17) 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
Shabdar 03/25/08 11:57:26 AM EDT

If you are looking for Google Maps control for ASP.Net visit following link,

http://www.shabdar.org

This is a free open source control.

Steve 06/02/06 11:11:07 AM EDT

The title of the article is misleading. I see no mention of Google Maps in the content of the article in regards to ASP.NET.

I applaud the editors for coming up with such innovatively misleading bait to entice them to read the entire article, and all the embedded ads. Bravo!

AJAX News Desk 06/01/06 11:59:33 AM EDT

In the past few months, the design pattern of combining Asynchronous JavaScript and XML (AJAX) to develop highly interactive Web applications has been growing in popularity. High-profile Web applications such as Google Maps and A9 are currently leveraging the combination of these technologies to produce rich client-side user experiences. The individual technologies that compose AJAX are not recent developments; they have been around for some time and have been continuously updated and improved. However, it is the recent confluence of these technologies that is leading to interesting possibilities.

SYS-CON India News Desk 05/31/06 12:50:59 PM EDT

In the past few months, the design pattern of combining Asynchronous JavaScript and XML (AJAX) to develop highly interactive Web applications has been growing in popularity. High-profile Web applications such as Google Maps and A9 are currently leveraging the combination of these technologies to produce rich client-side user experiences. The individual technologies that compose AJAX are not recent developments; they have been around for some time and have been continuously updated and improved. However, it is the recent confluence of these technologies that is leading to interesting possibilities.

SYS-CON Italy News Desk 05/31/06 12:20:35 PM EDT

In the past few months, the design pattern of combining Asynchronous JavaScript and XML (AJAX) to develop highly interactive Web applications has been growing in popularity. High-profile Web applications such as Google Maps and A9 are currently leveraging the combination of these technologies to produce rich client-side user experiences. The individual technologies that compose AJAX are not recent developments; they have been around for some time and have been continuously updated and improved. However, it is the recent confluence of these technologies that is leading to interesting possibilities.

AJAX News Desk 05/31/06 11:49:13 AM EDT

In the past few months, the design pattern of combining Asynchronous JavaScript and XML (AJAX) to develop highly interactive Web applications has been growing in popularity. High-profile Web applications such as Google Maps and A9 are currently leveraging the combination of these technologies to produce rich client-side user experiences. The individual technologies that compose AJAX are not recent developments; they have been around for some time and have been continuously updated and improved. However, it is the recent confluence of these technologies that is leading to interesting possibilities.

not amused 02/23/06 03:57:06 AM EST

unreadable text thanks to floating add that is impossible to close

Sanjay Gupta 02/21/06 04:41:58 PM EST

Great explaination of the article.
I appreciate it!

Sanjay

SYS-CON Italy News Desk 02/19/06 05:53:45 PM EST

In the past few months, the design pattern of combining Asynchronous JavaScript and XML (AJAX) to develop highly interactive Web applications has been growing in popularity. High-profile Web applications such as Google Maps and A9 are currently leveraging the combination of these technologies to produce rich client-side user experiences. The individual technologies that compose AJAX are not recent developments; they have been around for some time and have been continuously updated and improved. However, it is the recent confluence of these technologies that is leading to interesting possibilities.

news 12/23/05 04:31:18 PM EST

In the past few months, the design pattern of combining Asynchronous JavaScript and XML (AJAX) to develop highly interactive Web applications has been growing in popularity. High-profile Web applications such as Google Maps and A9 are currently leveraging the combination of these technologies to produce rich client-side user experiences. The individual technologies that compose AJAX are not recent developments; they have been around for some time and have been continuously updated and improved. However, it is the recent confluence of these technologies that is leading to interesting possibilities.

SYS-CON UK News Desk 12/23/05 02:32:15 PM EST

Google Maps! Ajax-Style Web Development Using ASP.NET
In the past few months, the design pattern of combining Asynchronous JavaScript and XML (AJAX) to develop highly interactive Web applications has been growing in popularity. High-profile Web applications such as Google Maps and A9 are currently leveraging the combination of these technologies to produce rich client-side user experiences. The individual technologies that compose AJAX are not recent developments; they have been around for some time and have been continuously updated and improved. However, it is the recent confluence of these technologies that is leading to interesting possibilities.

AJAX News Desk 12/23/05 11:41:04 AM EST

In the past few months, the design pattern of combining Asynchronous JavaScript and XML (AJAX) to develop highly interactive Web applications has been growing in popularity. High-profile Web applications such as Google Maps and A9 are currently leveraging the combination of these technologies to produce rich client-side user experiences. The individual technologies that compose AJAX are not recent developments; they have been around for some time and have been continuously updated and improved. However, it is the recent confluence of these technologies that is leading to interesting possibilities.

AJAX News Desk 12/23/05 10:42:12 AM EST

In the past few months, the design pattern of combining Asynchronous JavaScript and XML (AJAX) to develop highly interactive Web applications has been growing in popularity. High-profile Web applications such as Google Maps and A9 are currently leveraging the combination of these technologies to produce rich client-side user experiences. The individual technologies that compose AJAX are not recent developments; they have been around for some time and have been continuously updated and improved. However, it is the recent confluence of these technologies that is leading to interesting possibilities.

Mike 11/14/05 02:21:56 PM EST

I am interested in Geo fencing...would any of the above technologies enable the development of a Google map which has geo fencing capabilities?

Thanks for any input,

Mike

News Desk 10/20/05 11:17:56 PM EDT

Google Maps! AJAX-Style Web Development Using ASP.NET. In the past few months, the design pattern of combining Asynchronous JavaScript and XML (AJAX) to develop highly interactive Web applications has been growing in popularity. High-profile Web applications such as Google Maps and A9 are currently leveraging the combination of these technologies to produce rich client-side user experiences. The individual technologies that compose AJAX are not recent developments; they have been around for some time and have been continuously updated and improved. However, it is the recent confluence of these technologies that is leading to interesting possibilities.

.NET News Desk 09/08/05 12:58:07 PM EDT

AJAX-Style Web Development Using ASP.NET
In the past few months, the design pattern of combining Asynchronous JavaScript and XML (AJAX) to develop highly interactive Web applications has been growing in popularity. High-profile Web applications such as Google Maps and A9 are currently leveraging the combination of these technologies to produce rich client-side user experiences. The individual technologies that compose AJAX are not recent developments; they have been around for some time and have been continuously updated and improved. However, it is the recent confluence of these technologies that is leading to interesting possibilities.

Mark Petersen 09/07/05 10:22:23 AM EDT

The AJAX.NET URL is not correct.

I believe what you are looking for is:
http://ajax.schwarz-interactive.de/csharpsample/default.aspx

This library works in ASP.NET 1.1 as well.

@CloudExpo Stories
The Internet of Things 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, demonstrated how to move beyond today's coding paradigm and shared the must-have mindsets for removing complexity from the develo...
SYS-CON Events announced today that MangoApps 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. 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.
Large scale deployments present unique planning challenges, system commissioning hurdles between IT and OT and demand careful system hand-off orchestration. In his session at @ThingsExpo, Jeff Smith, Senior Director and a founding member of Incenergy, will discuss some of the key tactics to ensure delivery success based on his experience of the last two years deploying Industrial IoT systems across four continents.
Redis is not only the fastest database, but it is the most popular among the new wave of databases running in containers. Redis speeds up just about every data interaction between your users or operational systems. In his session at 19th Cloud Expo, Dave Nielsen, Developer Advocate, Redis Labs, will share the functions and data structures used to solve everyday use cases that are driving Redis' popularity.
Basho Technologies has announced the latest release of Basho Riak TS, version 1.3. Riak TS is an enterprise-grade NoSQL database optimized for Internet of Things (IoT). The open source version enables developers to download the software for free and use it in production as well as make contributions to the code and develop applications around Riak TS. Enhancements to Riak TS make it quick, easy and cost-effective to spin up an instance to test new ideas and build IoT applications. In addition to...
Predictive analytics tools monitor, report, and troubleshoot in order to make proactive decisions about the health, performance, and utilization of storage. Most enterprises combine cloud and on-premise storage, resulting in blended environments of physical, virtual, cloud, and other platforms, which justifies more sophisticated storage analytics. In his session at 18th Cloud Expo, Peter McCallum, Vice President of Datacenter Solutions at FalconStor, discussed using predictive analytics to mon...
Identity is in everything and customers are looking to their providers to ensure the security of their identities, transactions and data. With the increased reliance on cloud-based services, service providers must build security and trust into their offerings, adding value to customers and improving the user experience. Making identity, security and privacy easy for customers provides a unique advantage over the competition.
In his session at @DevOpsSummit at 19th Cloud Expo, Yoseph Reuveni, Director of Software Engineering at Jet.com, will discuss Jet.com's journey into containerizing Microsoft-based technologies like C# and F# into Docker. He will talk about lessons learned and challenges faced, the Mono framework tryout and how they deployed everything into Azure cloud. Yoseph Reuveni is a technology leader with unique experience developing and running high throughput (over 1M tps) distributed systems with extre...
"We've discovered that after shows 80% if leads that people get, 80% of the conversations end up on the show floor, meaning people forget about it, people forget who they talk to, people forget that there are actual business opportunities to be had here so we try to help out and keep the conversations going," explained Jeff Mesnik, Founder and President of ContentMX, in this SYS-CON.tv interview at 18th Cloud Expo, held June 7-9, 2016, at the Javits Center in New York City, NY.
SYS-CON Events announced today that Isomorphic Software will exhibit at DevOps Summit at 19th International Cloud Expo, which will take place on November 1–3, 2016, at the Santa Clara Convention Center in Santa Clara, CA. Isomorphic Software provides the SmartClient HTML5/AJAX platform, the most advanced technology for building rich, cutting-edge enterprise web applications for desktop and mobile. SmartClient combines the productivity and performance of traditional desktop software with the simp...
"When you think about the data center today, there's constant evolution, The evolution of the data center and the needs of the consumer of technology change, and they change constantly," stated Matt Kalmenson, VP of Sales, Service and Cloud Providers at Veeam Software, in this SYS-CON.tv interview at 18th Cloud Expo, held June 7-9, 2016, at the Javits Center in New York City, NY.
"There's a growing demand from users for things to be faster. When you think about all the transactions or interactions users will have with your product and everything that is between those transactions and interactions - what drives us at Catchpoint Systems is the idea to measure that and to analyze it," explained Leo Vasiliou, Director of Web Performance Engineering at Catchpoint Systems, in this SYS-CON.tv interview at 18th Cloud Expo, held June 7-9, 2016, at the Javits Center in New York Ci...
As companies gain momentum, the need to maintain high quality products can outstrip their development team’s bandwidth for QA. Building out a large QA team (whether in-house or outsourced) can slow down development and significantly increases costs. This eBook takes QA profiles from 5 companies who successfully scaled up production without building a large QA team and includes: What to consider when choosing CI/CD tools How culture and communication can make or break implementation
Internet of @ThingsExpo, taking place November 1-3, 2016, at the Santa Clara Convention Center in Santa Clara, CA, is co-located with the 19th International Cloud Expo and will feature technical sessions from a rock star conference faculty and the leading industry players in the world and ThingsExpo Silicon Valley Call for Papers is now open.
Extreme Computing is the ability to leverage highly performant infrastructure and software to accelerate Big Data, machine learning, HPC, and Enterprise applications. High IOPS Storage, low-latency networks, in-memory databases, GPUs and other parallel accelerators are being used to achieve faster results and help businesses make better decisions. In his session at 18th Cloud Expo, Michael O'Neill, Strategic Business Development at NVIDIA, focused on some of the unique ways extreme computing is...
"We view the cloud not really as a specific technology but as a way of doing business and that way of doing business is transforming the way software, infrastructure and services are being delivered to business," explained Matthew Rosen, CEO and Director at Fusion, in this SYS-CON.tv interview at 18th Cloud Expo, held June 7-9, 2016, at the Javits Center in New York City, NY.
Aspose.Total for .NET is the most complete package of all file format APIs for .NET as offered by Aspose. It empowers developers to create, edit, render, print and convert between a wide range of popular document formats within any .NET, C#, ASP.NET and VB.NET applications. Aspose compiles all .NET APIs on a daily basis to ensure that it contains the most up to date versions of each of Aspose .NET APIs. If a new .NET API or a new version of existing APIs is released during the subscription peri...
Organizations planning enterprise data center consolidation and modernization projects are faced with a challenging, costly reality. Requirements to deploy modern, cloud-native applications simultaneously with traditional client/server applications are almost impossible to achieve with hardware-centric enterprise infrastructure. Compute and network infrastructure are fast moving down a software-defined path, but storage has been a laggard. Until now.
"My role is working with customers, helping them go through this digital transformation. I spend a lot of time talking to banks, big industries, manufacturers working through how they are integrating and transforming their IT platforms and moving them forward," explained William Morrish, General Manager Product Sales at Interoute, in this SYS-CON.tv interview at 18th Cloud Expo, held June 7-9, 2016, at the Javits Center in New York City, NY.
To leverage Continuous Delivery, enterprises must consider impacts that span functional silos, as well as applications that touch older, slower moving components. Managing the many dependencies can cause slowdowns. See how to achieve continuous delivery in the enterprise.