CS603 Microsoft.NET April 8, 2002

What is.NET? Language for distributed computation –C#, VB.NET, JScript Protocols –SOAP, HTTP Run-time environment –Common Language Runtime (CLR) –ActiveDirectory –Web Servers (ASP.NET)

COM/DCOM .NET DCOM IDL Name, Monikers Registry / ActiveDirectory C++, Visual Basic DCE RPC DCOM Network protocol (based on DCE standards).NET Web Services Description Language (WSDL) DISCO (URI grammar) Universal Description Discovery and Integration (UDDI) C#, VB.NET SOAP HTTP (presumed ubiquitous), SMTP (!?)

How.NET works Query UDDI directory to get service location Query service to get WSDL (interface specification) Build call (XML) based on WSDL spec. Make call using SOAP Parse XML results based on WSDL spec.

Programming framework: ASP.NET Integrated environment –Web server: application deployment –Compiler: Just-in-time compilation –Development tools Implements Common Language Runtime –Base class library Looks like a web server –“Programs” stored/executed anywhere in hierarchy

Building.NET services ASP.NET –Manages compilation, run-time system, registration, etc. Hello.asmx using System; using System.Web.Services; public class Hello : WebService { [WebMethod] public String SayHello(String from) { Return "Hello, “ + from; } } Place in desired location of ASP.NET directory structure –Gives URL to execute

Alternative: Forms-based Development File test.aspx Name: Category: psychology business "> Welcome to ASP.NET

Configuration / Settings Configuration parameters: –Security –Language –Compilation options –Session vs. sessionless –Caching –Etc. Written as XML in file web.config –Applies recursively to programs in directory containing web.config

Type System Primitive types Enum, Arrays, Structs Classes (public fields/properties) DataSet –Tables –Schema XmlNode (XML fragment)

DataSets using System; using System.Data; using System.Data.SqlClient; using System.Web.Services; public class DataService { [WebMethod] public DataSet GetTitleAuthors() { SqlConnection myConnection = new SqlConnection("server=(local)\\NetSDK;database=pubs;Trusted_Connection=yes"); SqlDataAdapter myCommand1 = new SqlDataAdapter ("select * from Authors", myConnection); SqlDataAdapter myCommand2 = new SqlDataAdapter("select * from Titles", myConnection); DataSet ds = new DataSet(); myCommand1.Fill(ds, "Authors"); myCommand2.Fill(ds, "Titles"); return ds;}

Sessions Session: language-level access to cookies [ WebMethod(EnableSession=true) ] public String UpdateHitCounter() { return “Your access number " + ++Session["HitCounter"]; } Application: Stored state of server [ WebMethod ] public String UpdateHitCounter() { return “Total access number " + ++Application["HitCounter"]; }

Security Authentication –Windows –Passport –Forms-based authentication (cookie-based, login page) Access Control –Access Control List on file –Check against URL Configured using application configuration file: Can run either as self or impersonate caller

Tools “Visual” language environments: –VB.NET –C# Tracing –Page-level: Debug statements written to special section of output web page –Application-level: Debugging: Enable in configuration – –Breakpoint/stepping debugger run when service called

Announcements Monday, April 8, 3:30, CS 101 –David Holmes –Threads, concurrency and synchronization in Java Monday, April 15, 3:30, CS 101 –Philip McKinley –RAPIDware: Framework for adaptability in the face of error in distributed systems