Chapter 1- An Introduction To ASP Web Programming.ppt

1、Chapter 1: An Introduction To ASP.NET Web Programming,Liu, Jie,Professor Department of Computer Science Western Oregon University Liujwou.edu,Web Applications,The Client/Server model - a computation model for PCs to connect to other computers, like the monitor and mainframe architecture model. Clien

2、t sends a request Thin client Thick client Server answers the requests For Web based applications Communication are through HTTP (hypertext Transfer Protocol) What is a protocol Client is a browser such as IE (Internet Explorer) A browser displays pages defined using HTML tags (Hypertext, Markup Lan

3、guage) Static pages not going to change Dynamic pages formed dynamically according to the requests The application itself is defined on a web server such as IIS (Internet Information Services), with in turn may interact with other server such as a Database Management System (DBMS) that is hosted on

4、a database server,Web Applications,Domain name,Path,http:/sundown.wou.edu:81/en/mail.html?lang=en&laurel=on&cal=1,Protocol,Port,Page/file,Start of parameters,Parameter #1,Parameter #2,Dynamic Pages,A dynamic page is generated each time it is called The same page may be posted back to the server for

5、processing. Nevertheless, the page itself is stateless, i.e., it will not maintain the value of a variable between each loading of the page,More About State,“State” refers to the values of a variable or object Variables in a web page is stateless meaning that they do not “remember” their previous va

6、lues Methods used to maintain a variables state include Use view state Use session or application state object Using static variable (C# feature) Use cookie Use database (show Website 3 example and Visual Studio),A Closer Look at the example,The .ASPX page Page directives AutoEventWireup allows Page

7、_Load linked with page load event and called when the page is loaded The .ASPX.CS pageusing System.Web.UI.HtmlControls;public partial class _Default : System.Web.UI.Page protected void Page_Load(object sender, EventArgs e) if (IsPostBack) ,A Closer Look at the example,More about the Visual Studio in

8、 coming chapters A page and a page behind it (separation of presentation and business logic) Controls, properties, and events If I change nTemp to be a static variable, what will happen? Different between design view and source view,The .Net Framework Structure,Remote usersover Internet Any Browser,

9、Remote Systems Over Internet Any Hardware/OS,Local users Traditional Window application,ASP.NETApplication Services,Web Forms,Web Services,Windows Forms Controls Windows Application Services,.Net Compliant Programming Languages * VB.NET, C+, C#, J+, etc,.Net Framework Class Library Common Language R

10、untime,Operating System Windows 2000/2003/NT/98/ME/XP and may be other OSs,.Net Framework,VB, C#, and J+,/ Declare and initialize a string.string strFruit = “oranges,apples,peaches,kumquats,nectarines,mangos“; / Declare an array. string arrFruit; / Place each word in an array element. arrFruit = str

11、Fruit.Split(new Char , ., :); / Sort the array. System.Array.Sort(arrFruit); / Put the sorted array back in the string. strFruit = System.String.Join(“ “, arrFruit);,Summary,Have general understanding about the following Web applications Web page Stateless ASP.NET components (IIS, frame work, CLR, etc) Client/Server Dynamic pages URL Helpful web sites www.A,