Dot Net Over

1

Modern Software Development in .NET Modern Software Development in .NET and C#and C#

<< >><< >>

2

Session PrerequisitesSession Prerequisites

This is an This is an introintro of how .NET executes an of how .NET executes an appapp

Prereqs:Prereqs:developer developer

object-based programming experience object-based programming experience

3

Today's objectivesToday's objectives

““The days of compiling and linking a program to produce a The days of compiling and linking a program to produce a single native executable (.EXE) are coming to an end. single native executable (.EXE) are coming to an end. While program execution in WindowsWhile program execution in Windows®® has long been has long been DLL-based (dynamic linking), with .NET we are moving DLL-based (dynamic linking), with .NET we are moving towards a virtual machine model of execution…towards a virtual machine model of execution…””

Topics:Topics:Managed ExecutionManaged Execution

Component-Based DesignComponent-Based Design

Deployment Deployment

4

AgendaAgenda

Managed ExecutionManaged Execution


Assembly ResolutionAssembly Resolution

DeploymentDeployment

5


Idea:Idea:modern software executes within run-time modern software executes within run-time environmentenvironment

why? portable and safer execution…why? portable and safer execution…

HardwareHardware

Operating SystemOperating System

Run-time EnvironmentRun-time Environment

Your ApplicationYour Application

6

JavaJava

Based on run-time environment called Based on run-time environment called JVMJVM

JVM = Java Virtual MachineJVM = Java Virtual MachineJCL = Java Class LibraryJCL = Java Class Library

x86x86

WindowsWindows

JVMJVM

PPCPPC

Mac OSMac OS

JVMJVM

ARMARM

Palm OSPalm OS

JVMJVM

Java ApplicationJava Application

……

……

JVMJVM

JCLJCL

7

.NET.NET

Based on Based on CLRCLR and and FxCLFxCLCLR = Common Language RuntimeCLR = Common Language Runtime

FxCL = Framework Class LibraryFxCL = Framework Class Library

HardwareHardware

Operating SystemOperating System

Common Language RuntimeCommon Language Runtime

.NET Application.NET Application .NET Framework.NET FrameworkClass LibraryClass Library

8

Software Development in .NETSoftware Development in .NET

Pick your language and platform…Pick your language and platform…

x86x86

WindowsWindows

CLRCLR

ARMARM

Pocket PCPocket PC

CLRCLR

PPCPPC

FreeBSDFreeBSD

CLRCLR

x86x86

LinuxLinux

CLRCLR

……

……

CLRCLR

.NET Application.NET Application FxCLFxCL

VBVB C#C# C++C++ J#J# ……

9

Implications…Implications…

Your clients Your clients mustmust have the .NET have the .NET FrameworkFramework

available via available via Redistributable .NET FrameworkRedistributable .NET Framework (20MB) (20MB)

3 versions: v1.0 (2002), v1.1 (2003), v2.0 (june 3 versions: v1.0 (2002), v1.1 (2003), v2.0 (june 2005?)2005?)

Windows 2003 ships with v1.1Windows 2003 ships with v1.1

otherwise correct version must be installedotherwise correct version must be installed

Design trade-off:Design trade-off: portableportable safer execution (memory management, safer execution (memory management,

security, …)security, …) slower?slower?

10

Managed code Managed code

C#, VB, J# compilers generate C#, VB, J# compilers generate managedmanaged codecode

code that requires CLR to run & managecode that requires CLR to run & manage

C++ plays a dual role:C++ plays a dual role:generates generates managedmanaged code (i.e. .NET dll/exe) code (i.e. .NET dll/exe)

generates generates unmanagedunmanaged code (i.e. native code (i.e. native dll/exe)dll/exe)

common for OS work, legacy apps, etc.common for OS work, legacy apps, etc.

11

CILCIL

CIL = CIL = Common Intermediate LanguageCommon Intermediate LanguageCIL is the assembly language of the CLRCIL is the assembly language of the CLR

managed code == CIL codemanaged code == CIL code

// adds 2 integers together and returns the result…public int Add(int x, int y){ return x + y;}

C:\> ildasm app.exe

12

AgendaAgenda





13

Apps are Component-BasedApps are Component-Based

Apps consist of 1 or more components Apps consist of 1 or more components (DLLs)(DLLs)

Example:Example:typical n-tier designtypical n-tier design

Front-end

object object

object

DB

GUI.exeGUI.exe business.dllbusiness.dll data.dlldata.dll

14

.NET is Component-Based.NET is Component-Based

CLR and FxCL are components:CLR and FxCL are components:

CLR = Common Language RuntimeFxCL = Framework Class Library

CLR (MSCOREE.dll)

CLR (MSCOREE.dll)

JIT Compiler

Process

Underlying OS and HW

Core FxCL

(MSCOR

LIB.dll)

Core FxCL

(MSCOR

LIB.dll)

.DLL.DLL.DLL.DLL.EXE.EXE

obj code

additional FxCL components (DLLs)


15

AssembliesAssemblies

.NET components are called .NET components are called assembliesassemblies

Unit of deployment in .NETUnit of deployment in .NET1 assembly = 1 or more compiled source files1 assembly = 1 or more compiled source files

Visual Studio .NET

.EXE / .DLL.EXE / .DLL

code.vbcode.vbcode.vbcode.vb

code.cscode.cs

assembly

16

Where are FxCL assemblies?Where are FxCL assemblies?

FxCL assemblies are stored in the GACFxCL assemblies are stored in the GACGAC = GAC = Global Assembly CacheGlobal Assembly Cache

LocalLocal

SharedShared

Version-awareVersion-aware

SecureSecure

Tamper-proofTamper-proof

Some pre-JITSome pre-JIT

17

AgendaAgenda





18


CLR must be able to locate correct CLR must be able to locate correct assembliesassemblies

FxCL assemblies as well as our own assembliesFxCL assemblies as well as our own assemblies

CLR CLR

JIT Compiler

Process

Core FxCL

Core FxCL

.DLL.DLL.DLL.DLL.EXE.EXE

obj code



19

Resolution AlgorithmResolution Algorithm

1.1. .NET figures out what version is needed.NET figures out what version is needed

2.2. .NET searches GAC (.NET searches GAC (Global Assembly Global Assembly CacheCache))

3.3. If not found and .config file is presentIf not found and .config file is present then .NET searches where then .NET searches where

configured toconfigured to elseelse

.NET searches directory .NET searches directory containing .EXEcontaining .EXE

4.4. If not foundIf not found then application terminates with then application terminates with errorerror

20

How does .NET know version, How does .NET know version, etc.?etc.?Compiled into .DLL/.EXE as Compiled into .DLL/.EXE as manifestmanifest

use use ILDASMILDASM tool to peek inside assembly tool to peek inside assemblyILDASM = ILDASM = Intermediate Language DisassemblerIntermediate Language Disassemblermanifest reveals dependencies, versions, etc.manifest reveals dependencies, versions, etc.

C:\> ildasm CustomerGUI.exe

21

Observations…Observations…

Manifest contains Manifest contains referencereference to assembly to assemblyname, version #, hash of public key token, etc.name, version #, hash of public key token, etc.

Manifest does Manifest does notnot contain: contain:code for assemblycode for assembly

registry information (no more GUIDs!)registry information (no more GUIDs!)

location information (.NET uses search path)location information (.NET uses search path)

22

How are assemblies referenced?How are assemblies referenced?

Tracked via Tracked via ReferencesReferences folder in VS folder in VS projectproject

You can add more:You can add more:

23

AgendaAgenda





24

That’s it for today!That’s it for today!

Thank you for participatingThank you for participating

Dot Net Over

Documents

Transcript of Dot Net Over