Before ASP.NET, developers using Microsoft products had two paths they could take: Developers could either create simple HTML pages or they could use Active Server Pages (ASP). Obviously, there were other choices as well, including several techniques superceded by ASP. The next two sections outline the two existing techniques for creating Web applications.
Using HTML to Create Sites
You can create a Web site using nothing but HTML if you want. However, when you do this, you do not have the ability to provide any runtime customization. For example, suppose you have a product catalog. If you wish to add or delete items from the catalog, you have to go into the HTML page that has the products and manually add and delete these products. This can be quite laborious.
The following page, Page1.htm, provides simple support for submitting data to another page using a submit button:
<HTML> <BODY> <H3>Enter Login Information</H3> <form action="Process.htm" method="post"> Login ID <input type="textbox" value="BJones" name="txtLoginID"><br> Password <input type="password" name="txtPassword"><BR> <input type="submit" value="Login" name="btnLogin"> </FORM> </BODY> <HTML>
This page contains a Form element, which in turn contains all the data you might want to post to a page on your Web server. In this case, when you click Submit, you'll navigate to a page named Process.htm (which doesn't exist, in this little example). This page would need to somehow retrieve the values sent to it via the HTTP request. Luckily, you won't need to use this technique.
Microsoft realized the limitations of creating active Web sites using HTML and created Active Server Pages (ASP). (Microsoft wasn't alone in this there are other, competing technologies, as well, that provide similar functionality.) This technology allowed some script to run on the server, and the final output of this script was HTML. That is, the request to the page would cause script code to run, which in turn could render HTML for display in any browser. For example, the script could retrieve data from a table in a database and generate a product catalog dynamically.
The following page, Page1.asp, demonstrates how ASP applications might appear. Notice the mixture of HTML and script code that was the nature of the ASP beast. If you want to run this page, you'll need to set up a virtual root in IIS, load the page into that folder, and then browse to the server from within a browser. (In other words, you can't simply double-click ASP pages and view them in a browser they require processing by IIS in order to render their output.) Here's the code for the page:
<% Dim strLogin Dim strPassword ' First time through, no data strLogin = Request("txtLoginID") strPassword = Request("txtPassword") %> <HTML> <BODY> <H3>Enter Login Information</H3> <FORM action="Page1.asp" method="POST"> Login ID <input type="textbox" value="" name="txtLoginID"><br> Password <input type="password" value="" name="txtPassword"><BR> <input type="submit" value="Login" name="btnLogin"> <div><p><%= strLogin %> - <%= strPassword %></div> </FORM> </BODY> <HTML>