Creating Web Sites Before ASP.NET

来源:互联网 发布:windows电脑管理工具 编辑:程序博客网 时间:2024/05/15 11:10
Creating Web Sites Before ASP.NET
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including several techniques superceded by ASP.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.

Using ASP
Microsoft realized the limitations of creating active Web sites using HTML
and created Active Server Pages (ASP). (Microsoft wasn't alone in this梩here
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梩hat 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梩hey 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>
原创粉丝点击