Active Server Pages ASP.Net Jim Fawcett CSE686 – Internet Programming Summer 2005

Important Note! You can’t run Asp.Net applications – those with .aspx extensions – from the current college server. It does not have .Net installed. I will be running .Net applications from a new server that does have .Net installed and will become the college server sometime soon. You can run all the applications from the lecture #5 web page, as that links to the new server.

Moving Your Projects Visual Studio, by default, will build Asp.Net applications in two files: Web site files are placed in a folder with the project name under: C:\inetpub\wwwroot. Your solution and project files go in a folder with the project name under: C:\Documents and Settings\YourAccountName\ My Documents\Visual Studio Projects\ You can move the website folder into any parent directory you wish as long as you do two things: Make the new directory virtual and enable annonamous access Edit the WebApplication.csproj.webinfo to provide the correct url. Make sure the Application name shows in the virtual directory properties on the Virtual Directory tab. You may have to hit Remove and Add.

Changing Project Virtual Directories

Server-Side Programs You can run any .Net executable that resides in a virtual directory simply by requesting it from a browser: http://localhost/http://localhost/AspApps/PickCourse/PickForm.aspx Provided that directory permissions allow this. On Windows platforms most server-side processing takes the form of Active Server Page (ASP) applications or ASP.Net applications. Note that the examples I’ve placed on the college server will not run from there, as that server does not have .Net installed. To run the examples, just FTP the code folder to any directory on your local machine, in Windows Explorer right click on the folder, select properties, and select web sharing. Now you can open, for example, drives.aspx with the browser URL: http://localhost/lecture5/drives.aspx

Traditional ASP Traditional (pre .Net) ASP provides interpreted application scripts running in the memory space of the IIS web server. A traditional ASP page consists of a mix of HTML, sent directly to the requesting browser and Javascript or Vbscript executed on the server, usually to generate html for display or interact with a backend database. Traditional ASP uses a set of standard server side COM objects and can use custom COM objects as well. Deploying custom COM objects to remote servers has been a major problem.

Server-Side Objects Traditional ASP provides seven objects used for server-side programming: Application: starts when IIS starts and runs until IIS shuts down ASPError ASPError object is returned by Server.GetLastError(), and has the properties: Source, Category, File, Line, Description, ASPDescription ObjectContext Access to COM+ objects Request: Provides methods: Form(), QueryString(), Cookies(), ServerVariables() Response: Provides methods: Write(), Clear(), End(), Flush(), Redirect(), Buffer, Expires, IsClientConnected(), PICS() Server: Provides methods: Execute(), Transfer(), MapPath(), URLEncode(), HTMLEncode(), GetLastError() Session: starts when a user requests first page and ends with a timeout

ASP .Net ASP.Net supports the traditional style, but adds processing power of compiled C# and a pervasive object model. We can create user-defined classes in C# and use them on ASP pages. Any .Net language can be used this way. Web controls are based on CLR objects. Control state is sent back and forth between client and server. An ASP.Net page can easily be turned into a server control that can be used on any other ASP page. ../lectures/cse686codeL5.htm

ASP Environment

ASP Page Contents An ASP page can contain: Instructions for the server HTML content, intended for the client Code in C#, VB, Jscript.Net. The Code will: generate HTML for client get or send data to a database on this or a remote server interact in some way with the server’s file system Traditional script, e.g.: Javascript or Vbscript Embedded ASP.Net server controls Means to collect information from, and present information to, client Control state is preserved in transactions between client and server Traditional HTML controls Also manages information between client and server. Preserving state requires more work on programmer’s part.

ASP Applications You can build an ASP application using notepad to create an aspx page, a C# code page, and a web.config file. c:\su\cse686\code\AspApps\BasicAsp http://localhost/AspApps/BasicAsp/PickAgain.aspx Most often, you will build ASP solutions using Visual Studio.net.

ASP.Net Application Files An ASP Application generated by the Visual Studio.Net application wizard consists of: A solution in the local directory you chose for building the app: A set of files in a virtual directory on your development machine. When the application is complete you will simply copy these files to the web server you want to use to deploy the application. c:\su\cse686\code\aspapps\pickCourse http://localhost/AspApps/PickCourse/PickForm.aspx

ASP Application Files (continued) WebForm1.aspx An ASP page providing the user interface for the application WebForm1.aspx.cs A C# WebForm, with structure somewhat like a WinForm Web.config Allows you to set debug tracing and other session related properties AssemblyInfo.cs Holds assembly deployment information

Server Controls ASP.Net provides a number of Web controls based on HTML elements and HTML controls. Label, Button, TextBox, DropDownList, ListBox, Image, CheckBox, RadioButton, RadioButtonList, Calendar, Table, Panel, DataList, DataGrid, … These controls have state which is marshalled between client and server in a hidden ViewState variable. Events, like button clicks, that happen on the client side, are marshalled back to the server to trigger event handlers in C#, processed on the server.

Design View

ASPX Code View

C# Code View

Let’s Build an Application Create an ASP.Net Application, using C# Right click on form and set its layout property to flow layout. Pull a TextBox, Button, and Label onto the form. Switch to HTML view and put a couple of <br> tags between each of these controls. Double click on the form to generate a Page_Load event handler and we will put some code there. Double click on the button and we’ll also put some code there. Run the application.

References Programming Microsoft .Net, Jef Prosise, Microsoft Press, 2002 ASP.NET Unleashed, Second Edition, Stephen Walther, SAMS, 2004 ASP.Net, Tips, Tutorials, and Code, Mitchell, et. al., SAMS, 2002 More examples (a lot in Visual Basic.Net, some in C#) than most of the other books available on ASP. www.gotdotnet.com has some interesting tutorial material on ASP.Net.