.Net is a collection of libraries, templates and services designed to make programming applications of all kinds, easier, more flexible (multi platform), and more scalable

ASP.Net is a subset of .Net that contains tools for developing web based applications

A server is a program that makes services available to another program (a client)

For instance, A web server such as IIS (Internet Information Server) or Apache makes web pages available to a client application such as a browser

A database server makes data available to client that makes a valid request

ASP.Net pages are served from IIS when a browser requests an .apsx page.

IIS passes the request to .Net which processes the C# or VB code and ASP controls, makes any database requests and renders them into xhtml

IIS then sends the rendered page to the browser that made the request

The Page Web Form Html and ASP.Net Controls Code behind CSS

An ASP. Page can have only 1 form. A key attribute of the form is

runat=“server” which tells IIS to send it to .Net for compiling and rendering. (Plain html elements are just passed through to the client without any .net processing)

All asp controls must be contained within the form

An ASP.Net page can use plain xhtml Xhtml controls (xhtml with the

runat=“server” attribute added) ASP.Net controls, controls provided by .Net

Library Client side JavaScript

ASP.net pages have two views Design and Source

Design view shows controls approximately as they will appear on the rendered page (some info shown here won’t be displayed)

Source view shows the html and the asp.net controls.

ASP controls are represented as XML fragments Controls can be added in Design or source views

<asp:Label ID="Label1" runat="server" Text="Enter the Miles"></asp:Label>

ASP.Net allows you to write the code in a separate file.

This makes code easier to read and maintain

The page directive tells .Net where to find the code page.

Code can still be placed directly in the web page if you wish either between <script> tags or between <% %> brackets

ASP.Net supports CSS and has a good CSS editor

CSS classes and styles can be added to a ASP control by using the CssClass attribute

<asp:TextBox ID="txtMiles" runat="server" CssClass="entry"></asp:TextBox>

ASP.Net, like all web pages are stateless. Every time you click and button or use control

that causes postback the page is re-rendered from the server

Information is not retained between postbacks without some additional programming. (Windows forms have state. They keep their variable values and contents in RAM)

This has several implications for web application development that we will have to examine later