Datasheet

returned to the terminal-style development. In this methodology, any major operation between the client

and server requires that all data be sent in what is called a round trip. With a round trip, all data from the

form is sent from the client to the web server. The web server processes data and then sends it back to the

client. The result of a round trip is that a lot of data is sent back and forth between the client and server.

Given the circumstances, these operations may result in more data transfer and CPU utilization than a

web application and server can really tolerate.

ASP.NET Development

ASP.NET is a set of web development technologies produced by Microsoft that is used to build dynamic

web sites, web applications, and XML-based web applications. ASP.NET is a part of the .NET framework

and allows for developers to build applications in multiple languages, such as Visual Basic .NET, JScript

.NET, and C#.

Design Methodology

ASP.NET attempts to make the web development methodology like the GUI development methodology

by allowing developers to build pages made up of controls similar to a GUI. Server controls in ASP.NET

function similarly to GUI controls in other environments. Buttons, text boxes, labels, and datagrids have

properties that can be modified and expose events that may be processed. The ASP.NET server controls

know how to display their content in an HTML page just like GUI-based user controls know how to dis-

play themselves in their GUI environment. An added benefit of ASP.NET is that the properties and meth-

ods of the web server controls are similar, and in some cases the same as the comparable controls in the

Windows GUI/Windows Forms environment.

Problems ASP.NET Solves

Microsoft has released various web application development methodologies since the shipment of IIS in

Windows. Why do developers need ASP.NET? What problems does ASP.NET solve that the previous

development methodologies did not solve?

Microsoft’s first popular web development technology was the Internet Database Connector (IDC). The

IDC methodology provided only database access; it did not provide access to any other resource program-

matically. For example, there was no way to programmatically send email or do other non-database opera-

tions. Another issue was that it seemed to be somewhat different from the traditional programming

languages that most developers were used to (Visual Basic and C++ being two popular ones). Along

with this problem was the fact that the development experience was not very attractive within Microsoft

FrontPage. Along with the development experience, IDC had no debugging experience worth mention-

ing. Overall, IDC was nothing more than a stopgap measure to get to an improved environment.

The next web development methodology from Microsoft was Active Server Pages (ASP). ASP was a

scripting environment that allowed developers to work with a Visual Basic–like or JavaScript-type

environment. Unfortunately, this type of environment came with several problems:

❑ Prevalence of spaghetti code — ASP code does not provide a structured development environ-

ment, often contributing to the creation of twisted and tangled “spaghetti code.” ASP code is

literally a file with some basic configuration information at the top of every page. Each page

is executed from the top of the page to the bottom of the page. Although it is possible to use

Component Object Model (COM) objects to eliminate some of the spaghetti code, this intro-

duces more complexity in the form of another development tool.

Chapter 1: Introduction to ASP.NET AJAX

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