1. Introduction to .NET Manuel Costa manuelc@microsoft.com
Academic Computer Science Program Manager

2. What is .NET?
A development platform: interfaces, components and tools to develop software
The biggest change in the Microsoft platform since Windows NT replaced DOS
Changes include:
Code formats, compilers,
Code loading and execution models,
Security model,
Object model, metadata, remoting protocols
Class libraries, …

3. .NET: Principles The Microsoft Vision for Computing
Make Internet-scale distributed computing ubiquitous
Exploit inexpensive cycles and bandwidth
Seamless integration of multiple applications and devices
Deliver software as a service
Next generation user experience
The .NET Framework is the programming-model substrate for the .NET vision

4. Common Language Runtime
.NET Framework
Common Language Runtime (CLR)
Multi-language support
Common type system
Simplified deployment
Code Access Security
Rich Class libraries
Powerful, Consistent Programming Model
Focus on code, not plumbing
Built for Tools
Support for design-time functionality
Debugging, profiling, instrumentation support
ASP.NET
Web Forms Web Services
Mobile Devices
Windows
Forms
ADO.NET and XML
Base Class Library
Common Language Runtime

5. Common Language Runtime
DEVELOPMENT
Assembly
public static void Main(String[] args )
usr=Environment.GetEnvironmentVariable("USERNAME");
try {
{ String usr; FileStream f; StreamWriter w;
w.WriteLine(usr);
w=new StreamWriter(f);
f=new FileStream(“C:\\test.txt",FileMode.Create);
Console.WriteLine("Exception:"+e.ToString());
} catch (Exception e){
w.Close(); }
Compiler
public static void Main(String[] args )
usr=Environment.GetEnvironmentVariable("USERNAME");
try {
{ String usr; FileStream f; StreamWriter w;
w.WriteLine(usr);
w=new StreamWriter(f);
f=new FileStream(“C:\\test.txt",FileMode.Create);
Console.WriteLine("Exception:"+e.ToString());
} catch (Exception e){
w.Close(); }
Source code C# J# VB
Cobol …
CIL
Metadata
Resources

6. Common Language Runtime
Compiler
Assembly
DEVELOPMENT C# J# VB
Cobol …
CIL
Metadata
Resources
public static void Main(String[] args )
usr=Environment.GetEnvironmentVariable("USERNAME");
try {
{ String usr; FileStream f; StreamWriter w;
w.WriteLine(usr);
w=new StreamWriter(f);
f=new FileStream(“C:\\test.txt",FileMode.Create);
Console.WriteLine("Exception:"+e.ToString());
} catch (Exception e){
w.Close(); }
Source code
Assembly
DEVELOPMENT
DEPLOYMENT
Global Assembly Cache (GAC)
Install
Setup
Copy
Browser
Application Directory
Download Cache

7. Common Language Runtime
Assembly
DEVELOPMENT
Application Directory
Setup
Copy
Browser
Download Cache
DEPLOYMENT
Global Assembly Cache (GAC)
Assembly on Target Machine
Install
Policy
<security>
<mscorlib>
<configuration>
<?xml version="1.0" encoding="utf-8" ?>
<policy>
version="1"
<CodeGroup class="UnionCodeGroup"
<PolicyLevel version="1">
PermissionSetName="Nothing"
Description="Code group grants no permissio ns and forms the root of the code group tree.">
Name="All_Code"
<IMembershipCondition clas s="AllMembershipCondition"
version="1"/>
PermissionSetName="FullTrust"
EXECUTION
IL to Native Compiler
Class Loader
Security
Assembly
Loader
Garbage Collection
Native .exe + GC table
Code Manager
Exception Manager
Thread Support
COM Interop
Debug Engine

8. Demo
CLR

9. .NET Framework Namespace
System.Web
System.WinForms
Services UI
Design
ComponentModel
Description
HtmlControls
Discovery
WebControls
Protocols
System.Drawing
Caching
Security
Drawing2D
Printing
Configuration
SessionState
Imaging
Text
System.Data
System.Xml
ADO
SQL
XSLT
Serialization
Design
SQLTypes
XPath
System
Collections IO
Security
Runtime
InteropServices
Configuration
Net
ServiceProcess
Remoting
Diagnostics
Reflection
Text
Serialization
Globalization
Resources
Threading

10. .NET Framework Design Goals
Simplify application development
Provide a robust and secure execution environment
Support multiple programming languages
Simplify deployment and management

11. Simplify Development Windows API .NET Framework
HWND hwndMain = CreateWindowEx(
0, "MainWinClass", "Main Window",
WS_OVERLAPPEDWINDOW | WS_HSCROLL | WS_VSCROLL,
CW_USEDEFAULT, CW_USEDEFAULT,
(HWND)NULL, (HMENU)NULL, hInstance, NULL);
ShowWindow(hwndMain, SW_SHOWDEFAULT);
UpdateWindow(hwndMain);
.NET Framework
Form form = new Form();
form.Text = "Main Window";
form.Show();

12. Simplify Development Organization Unified type system
Code organized in hierarchical namespaces and classes
Unified type system
Everything is an object, no variants, one string type, all character data is Unicode
Component Oriented
Properties, methods, events, and attributes are first class constructs
Design-time functionality

13. Robust And Secure Automatic lifetime management
All .NET objects are garbage collected
No stray pointers, no circular references
Code correctness and type-safety
IL can be verified to guarantee type-safety
No unsafe casts, no uninitialized variables, no out-of-bounds array indexing
Evidence-based security
Based on origin of code as well as user
Extensible permissions

14. Multi-Language Platform
The freedom to choose language
All features of .NET platform available to any .NET programming language
Application components can be written in multiple languages
Debuggers, profilers, code coverage analyzers, etc. work for all languages
Available Compilers
From Microsoft: VB, C++, C#, JScript, Java
From other companies/universities: APL, COBOL, Eiffel, Fortran, Haskell, ML, Perl, Python, RPG, Scheme, Smalltalk, …

15. Unify Programming Models
.NET Framework
Consistent API availability regardless of
language and programming model
VB Forms
RAD,
Composition,
Delegation
MFC/ATL
Subclassing,
Power,
Expressiveness
ASP
Stateless,
Code embedded
in HTML pages
Windows API

16. Broad Language Support
Dim s as String
s = "authors"
Dim cmd As New SqlCommand("select * from " & s, sqlconn)
cmd.ExecuteReader()
VB.NET
string s = "authors";
SqlCommand cmd = new SqlCommand("select * from "+s, sqlconn);
cmd.ExecuteReader(); C#
C++
String *s = S"authors"; SqlCommand cmd = new SqlCommand(String::Concat(S"select * from ", s),
sqlconn); cmd.ExecuteReader();

17. Broad Language SupportJ#
String s = "authors";
SqlCommand cmd = new SqlCommand("select * from "+s, sqlconn);
cmd.ExecuteReader();

18. Broad Language Support
var s = "authors"
var cmd = new SqlCommand("select * from " + s, sqlconn)
cmd.ExecuteReader()
JScript
String *s = S"authors"; SqlCommand cmd = new SqlCommand(String::Concat(S"select * from ", s), sqlconn); cmd.ExecuteReader();
Perl
s = "authors"
cmd =SqlCommand("select * from " + s, sqlconn)
cmd.ExecuteReader()
Python

19. Broad Language Support
ENVIRONMENT DIVISION.
CONFIGURATION SECTION.
REPOSITORY.
CLASS SqlCommand AS "System.Data.SqlClient.SqlCommand"
    CLASS SqlConnection AS "System.Data.SqlClient.SqlConnection".
DATA DIVISION.
WORKING-STORAGE SECTION.
01 str PIC X(50).
01 cmd-string PIC X(50).
01 cmd OBJECT REFERENCE SqlCommand.
01 sqlconn OBJECT REFERENCE SqlConnection.
PROCEDURE DIVISION.
*> Establish the SQL connection here somewhere.
MOVE "authors" TO str.
STRING "select * from " DELIMITED BY SIZE,
   str DELIMITED BY " " INTO cmd-string.
INVOKE SqlCommand "NEW" USING BY VALUE cmd-string sqlconn RETURNING cmd.
INVOKE cmd "ExecuteReader".
Cobol

20. Broad Language Support
RPG
  DclFld MyInstObj Type( System.Data.SqlClient.SqlCommand )
 DclFld s Type( *string )
 s = "authors"
 MyInstObj = New System.Data.SqlClient.SqlCommand("select * from "+s, sqlconn)
 MyInstObj.ExecuteReader()
assembly_external(name="System.Data.SqlClient.SqlCommand")
sqlcmdcharacter*10 xsqlcmd
Cmd x='authors'
cmd = sqlcmd("select * from "//x, sqlconn)          
call cmd.ExecuteReader()
end 
Fortran

21. Broad Language Support
APL
s←String.New ‘authors’
cmd←SqlCommand.New (‘select * from ‘,s.ToString σ) sqlconn
cmd.ExecuteReader
    |s| := 'authors'.
    |cmd| := SqlCommand('select * from '+s, sqlconn).
    cmd.ExecuteReader().
Smalltalk

22. Broad Language Support
(let* ( (s "authors")
  (cmd (new-SqlCommand (string-append "select * from " s) sqlconn)))
(execute-command cmd))
Scheme
local
      s: STRING
      cmd: SQLCOMMAND do
     s := "authors"
      create cmd("select * from " + s, sqlconn)
      cmd.ExecuteReader()
end
Eiffel
ExecuteReader = invoke System.Data.SqlClient.ExecuteReader();
SqlCommand = create System.Data.SqlClient.SqlCommand(String,\
System.Data.SqlClient.SqlConnection);
query = sqlconn -> let{ s = "authors"; } in {
   cmd <- SqlCommand ("select * from "+s, sqlconn);
  cmd # ExecuteReader();   
}; 
Mondrian

23. Demo
Language Integration