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Ramapo Masters of Science Tools and Concepts of Data Analysis: Dataweb Introduction to ASP (Home) Hypertext Markup Language (html) is the base language on which the Internet was developed. Through html you can create a web page that can display text, graphics (if saved in the correct format), hyperlinks, and form elements for collecting data. Html is very limited, however, in how the information collected from such elements can be processed. When an html (also known as htm) page is requested (either by clicking a hyperlink or through another method), the html code is sent from the server to the user's browser (Internet Explorer, Netscape, Firefox, Opera, Safari, etc.) which creates the graphical representation on the monitor. It is the browser, on the local machine, that interprets the html making this a "client side" process. The Internet was designed around this premise in order to make web pages universally accessible. It does not matter what kind of server sends the page because it is interpreted on the local computer. While this technology opened up a whole new world of communication, people soon wanted to expand the capabilities of their web pages. Support for JavaScript, a computer language developed for the Web, was soon added to major browsers. JavaScript, is also a "client side" technology as it is processed by the browser. The validation of form elements (text boxes, radio buttons, etc.) is often an example of JavaScript in action. When you attempt to submit a form on the Internet, but are stopped because of a missed or incorrectly completed field, it is likely that JavaScript is the reason. Because it is well supported by modern browsers, JavaScript is often used in web page design. When collecting information through the Internet, it is often most advantageous to store and process that information in a database. Neither html nor JavaScript have the capability of performing the tasks required to do so. In order to accomplish this, a user must choose a technology to augment the capabilities of these languages. Several options exist including CGI scripting, Cold Fusion Markup Language, php (Hypertext Preprocessor), and Active Server Pages (ASP). Browsers do not support any of these technologies directly, and so the processing of such pages must be done on a web server specifically configured to support the technology used. This is a "server side" process because the server must process parts of these pages before sending them to the user. ASP is a Microsoft technology which extends the functionality of web pages in many ways - one of which is in interactions with data sources such as a databases. Microsoft's first release of this technology was known as ASP, but they have since developed a related but more advanced technology known as ASP.NET. In both cases, web pages may include not only html and JavaScript but also additional languages supported by the framework. To this end, ASP pages most often use vbscript (a light version of visual basic designed for the web) or less frequently Jscript (Microsoft's own version of JavaScript). ASP.NET supports more powerful languages such as Visual Basic.net, C#, C + +, and others. As previously stated, the server must be specifically configured to process ASP pages of any type. When an ASP page is requested, the server first identifies the file type by checking the file extension. If it is .asp (ASP) or .aspx (ASP.NET), the server "parses" the page looking for code that can not be processed by the user's browser. It interprets this code, performs any functions required, and generates an html version of the result. Only then does it send the page to the user's browser. The browser receives only the html interpretation created by the server and uses it to create the graphical image on the user's monitor. It is in this way that dynamic pages are created using ASP. Site Designed and Maintained by rsciorra |