MICROSOFT .NET INTEROPERABILITY

FOR BEGINNERSVjekoslav Babic

(Fortempo)

Vjekoslav Babićconsultant, trainer, blogger, author

Twitter: @vjekobMibuso: VjekoBlog: vjeko.com

Author of many How Do I… videos for MSDN and PartnerSource for NAV 2013 and NAV 2013 R2

Co-author of “Implementing Microsoft Dynamics NAV 2009” book

ABOUT ME

HOW OTHER PEOPLE SEE PROGRAMMERS

HOW PROGRAMMERS SEE OTHER PEOPLE

Most of the time?

WHAT DO PROGRAMMERS REALLY DO?

SO, WHAT DO PROGRAMMERS DO MOST OF THE TIME?

% OF TOTAL TIME SPENT PROGRAMMING

% OF TOTAL TIME SPENT PROGRAMMING IN C/AL

37.5% OF ALL STATISTICS AREJUST MADE UPON THE SPOT

WHAT ARE WE DOING HERE TODAY?Basic Concepts• Constructors• Methods• Overloading• Events• Enumerations

Slightly Advanced Concepts• Classes and Interfaces• Arrays and Collections• Enumerators• Generics• Reflection• Creating Assemblies• Creating Control Add-ins

HOW ARE WE DOING IT?General conceptsManaging strings and textManaging dates, times, and numbersAccessing operating system, file system, and the environmentManaging data, arrays, collections, and streamsCustom assembliesClient Add-ins

PART ONEGeneral concepts

ASSEMBLIESBuilding blocks of the .NET Framework

Assemblies can be:• Executable files (EXE)• Dynamic Link Libraries (DLL)

Assemblies can be deployed to:• Single application: any folder accessible to a .NET application• All applications: Global Assembly Cache (GAC)

TYPE.NET Framework is strongly-typed, very similar to C/AL

Types can be:• Simple• Complex

.NET is object-oriented:• Types can be inherited

Two types of complex types:• Classes• Interfaces

CLASSES AND INTERFACESBoth represent complex types (types that contain members)

Classes:• Define the structure• Encapsulate functionality• One class can inherit from only one parent class

Interfaces:• Only define the structure, but not the functionality• Represent behaviors of classes• One class can implement multiple interfaces• By convention, names start with I, and many names end with …

able

THE DotNet DATA TYPEVariables of type DotNet give access to .NET Framework

Each DotNet variable specifies:• Assembly• Type

DotNet gives access to:• Methods• Properties• Constructors• Enumerations

IMPORTANT: CASE SENSITIVITYAll .NET Framework identifiers are CASE SENSITIVE

PART TWOManaging strings and text

System.StringA powerful class to handle text information.Maps fully and directly to Text data type in C/AL.

METHODSEquivalent to functions in C/AL

Methods are defined by their signature. Signature consists of:• Name• Type and kind of parameters (by value, by reference, or output)

Return value can be:• Of specific type• void

System.String POINTS OF INTEREST

Analyzing content

• StartsWith• EndsWith• Contains• IndexOf• IndexOfAny• IsNullOrWhiteSpace• LastIndexOf• LastIndexOfAny• Substring

Modifying content

• Insert• PadLeft• PadRight• Remove• Replace• Trim• TrimStart• TrimEnd

System.Text.StringBuilderA very powerful class to handle large text data efficiently.

CONSTRUCTORSCreate an instance of a class.

There is no equivalent in C/AL to constructors.CREATE function for instantiating automation objects is the closest

Typically used to:• Initialize the default state of an object• Execute default initialization logic• Limit instantiation

SYNTAX OF A CONSTRUCTORThe name of the constructor always matches the class name.

This probably looks confusing in C/AL:StringBuilder := StringBuilder.StringBuilder;

(why in the Earth do we need all those StringBuilders?)

Replace the StringBuilder variable name with s, and it’s more manageable:s := s.StringBuilder;

The syntax of the constructor in C/AL is the following:Variable := Variable.[Class Name]({argument1, …});

System.Diagnostics.StopwatchA simple and useful class to handle time measurements.

NAMESPACEA higher-level scope used to organize code

Namespace has a many-to-many relationship to assemblies:• One assembly can contain multiple namespaces• The same namespace can span multiple assemblies

System.Text.RegularExpressionsA namespace containing classes for managing regular expressions.

In case you didn’t know:• Regular Expressions (RegEx) are a language used for searching

text data through pattern matching• Regular Expressions are SQL of textual data

OVERLOADINGCapability that allows multiple members to use the same name as long as the signature remains different.

C/AL understands overloading of:• Methods• Constructors

.NET supports, but C/AL does not understand overloading of:• Indexers• Operators

PART THREEManaging dates, times, and numbers

System.DateTimeManages date and time information.Maps fully and directly to DateTime data type in C/AL.

Many useful properties and methods.

PROPERTIES AND FIELDSProperties and Fields are members of complex classes that contain a

value.

Property:• Always accessible from C/AL• Can be gettable, settable, or both

Field:• Never accessible from C/AL

System.GlobalizationNamespace that defines a lot of useful type for managing date and time formats, regional settings, cultures, etc.

Useful classes:• Calendar• CultureInfo• DateTimeFormatInfo• NumberFormatInfo

System.Globalization.CalendarManages time division into years, months, weeks, days, etc.

System.Globalization.CultureInfoProvides access to culture information. Cultures are the heart of the .NET localization/globalization functionality.

System.Globalization.DateTimeFormatInfoProvides access to date and time formatting information.

System.Globalization.NumberFormatInfoProvides access to number formatting information.

System.MathProvides methods for trigonometric, logarithmic, and other common mathematical functions.

System.Numerics.BigIntegerRepresents an arbitrarily large integer value, without any theoretical upper or lower bounds.

System.ConvertConverts a base data type to another base data type.

PART FOURAccessing operating system, file system, and the environment

System.IONamespace that provides many useful input and output classes.

System.IO.FileProvides static methods for the creation, copying, deletion, moving, and opening of files.

STATIC OBJECTS AND METHODSStatic classes cannot be instantiatedStatic methods can be called on classes

Static classes and members are shared for the whole application domain

Microsoft Dynamics NAV Server runs as a single application domain

System.IO.DirectoryExposes static methods for creating, moving, and enumerating through directories and subdirectories.

System.IO.PathPerforms operations on String instances that contain file or directory path information.

System.IO.FileSystemWatcherListens to the file system change notifications and raises events when a directory, or file in a directory, changes.

EVENTSEnable a class to notify other classes when something of interest

happens.

Equivalent to C/AL triggers.

Events are not automatically exposed.You must first set the WithEvents property.

Events can run be:• Server-Side: default behavior, if RunOnClient is No• Client-Side: if RunOnClient is Yes

EVENTS ARE NOT AS INNOCENT AS THEY APPEARWhenever using events, consider:• Client-Side events can only run in pages• Events can be synchronous and asynchronous• Event triggers are only created when the WithEvents is first set to

Yes

ENUMERATIONSTypes that consist of set of named constants.

Similar, but not nearly equal to C/AL options.

C/AL .NET

Always of Integer type Of any integer numeric type, except char

Always 0-based 0-based by default, but can be any value

Each consecutive element is increased by 1

Every element can have an explicit numeric value, even negative

SUPPORT FOR ENUMERATIONS IN C/SIDE

NAV 2009 R2 NAV 2013

Does not recognize them Recognizes them

You must use integers You can use named values

You cannot use bitwise operators (AND, OR, NOT, XOR).You can use + in place of OR, but that’s about it.

System.EnumEnables managing enumerations at runtime.

MANAGING TYPE INFORMATION AT RUNTIMESystem.TypeGETDOTNETTYPECANLOADTYPE

System.Diagnostics.EventLogProvides interaction with Windows event logs.

PART FIVEHandling data• Arrays• Collections• Streams

ARRAYS AND COLLECTIONSArrays:• Contain a fixed number of values of the same data type• Roughly correspond to C/AL arrays (variables with Dimensions

property)

Collections:• Contain an arbitrary, flexible number of values of the same data

type• No equivalent in C/AL

Both arrays and collections are extensively used in .NET

System.ArrayProvides methods for creating, manipulating, searching, and sorting

arrays.

Serves as the base class for all arrays in the common language runtime.

ENUMERATORSEnable iterating through arrays and collections.C# uses the foreach keyword to manage the iteration.

Two interfaces are in charge of the enumerator-based iteration:• IEnumerable<T>• IEnumerator<T>

IEnumerable<T>• Exposes the enumerator

IEnumerator<T>• Allows iteration through enumerable object• Current• MoveNext

System.Collections.SortedListRepresents a list of key/value pairs that are sorted.

System.Collections.HashTableRepresents a list of key/value pairs that are stored by using a hash

table.

System.Collections.Generic.List<T>Represents a strongly typed list of objects that can be accessed by

index.

Provides methods to search, sort, and manipulate lists.

GENERICSAllow a single design-time declaration that compiles to multiple run-time types.

List<T> can compile to List<int>, List<string>, or List<MyDesiredClass>

Supported on:• Classes and interfaces• Methods• Properties• Structures• Fields

In C/AL, all generics are of type System.Object

System.Collections.Generic.Dictionary<TKey,TValue>Represents a strongly typed collection of keys and values.

Provides fast methods to look up content.

System.TimeSpanContains a lot of functionality for managing timespans down to a resolution of 100 nanoseconds.

MAPPING .NET TYPES TO C/ALSome types map fully:• String• DateTime• InStream and OutStream

Many data types map uni-directionally:• Most simple data types (Boolean, Decimal, Integer, etc.)• Some complex data types (Duration)

You cannot use uni-directionally mapped .NET data types in C/AL directly.

REFLECTIONCapability of .NET to gain insight into itself.

Enables managing objects and calling their functionality at runtime without knowing much about the type at design time:• Discovering information about types• Loading assemblies• Instantiating objects• Executing methods• Getting and setting properties• And many more

System.IO.StreamA class that provides a generic view of a sequence of bytes.

Typical descendants:• System.IO.MemoryStream• System.IO.FileStream

Fully mutually interchangeable with both InStream and OutStream C/AL types.

Limitation:• CREATEOUTSTREAM and CREATEINSTREAM cannot be called on

System.IO.Stream

System.Net.WebClientProvides common methods for sending data to and receiving data from a resource identified by a URI.

PART SIXDeveloping Custom Assemblies

USING VISUAL STUDIOCreating an assemblyQuick overview of C# project structureAdding classes

DEPLOYING ASSEMBLIESClient deploymentService Tier deploymentGlobal Assembly Cache (GAC)

CLIENT DEPLOYMENTRequired for development and Must be deployed in:• 2009:<Program Files (x86)>\Microsoft Dynamics NAV\6.0\Classic

• 2013<Program Files (x86)>\Microsoft Dynamics NAV\6.0\RoleTailored Client<Program Files (x86)>\Microsoft Dynamics NAV\7.x\RoleTailored Client

Best practice:• Deploy in separate Add-ins subfolder

Assembly is loaded on first design access to the C/SIDE object which uses it

Client must be restarted to refresh the loaded assembly

SERVICE TIER DEPLOYMENTPer instance of NSTMust be deployed in:<Program Files>\Microsoft Dynamics NAV\x.y\<Service>

Best practice:• Deploy in separate Add-ins subfolder

Deployed assembly is loaded on first callNST must be restarted to refresh the assembly

GLOBAL ASSEMBLY CACHE (GAC)Central repository of known .NET assembliesMachine-wideOnce registered in GAC, assembly is accessible from anywhere

in .NETAllows side-by-side execution of different code versionsRequirements:VersioningStrong naming with a public keyDeployment to GAC

GLOBAL ASSEMBLY CACHE AND C/SIDEC/SIDE is aware of the GACObjects deployed to GAC are not required to be deployed to Add-ins

SIMPLIFYING DEPLOYMENTAlways strongly sign assembliesUse Post Build eventsAlways deploy to GAC

PART SEVENDeveloping Client Add-ins

DEVELOPING ADD-IN CONTROLSCreating add-in controlsDeploying add-in controlsConsuming add-in controls