BusinessLayer Builder

New version of "basi"(0.2.1)

2008-12-05T17:15:00.002+01:00

I've just released the version 0.2.1 of "basi".
Changes made to the class EntityBase are intended to get a rid of time wasting pieces of code.

Features requests codes are :
2392350 useless overhead of ID and DataModifica properties
2392345 with (nolock) statement in SQL select
2392343 StringBuilder to build dynamic SQL code
2392341 Use of Generics

Now this class needs at least .NET 2.0

Let's stop war!

2006-11-24T13:15:00.000+01:00

This is a very interesting event! www.globalorgasm.org to change the energy field of the earth, let's make love!
I think that's such a strange thing, but I'm going to partecipate, me and my ex girlfiried! Let's make love as much as you can.

Entity HOW-TO

2006-10-05T10:52:00.000+02:00

Using the entities HOW-TO

There is a class for each table, using those classes you can instantiate entities wich can be persistant.
To do this, you have to take a look at the base classes, RecordBase, Column, EntityList.
Each entity class inherits RecordBase, wich contains methods and attributes that allows the subclass to read, write (insert or update) and delete a record in the database. The subclass is just a RecordBase class with a fixed table schema and properties to access values of fields.

e.g.
Dim user As New User

user is an entity of type “User”, you can create a new user...

user.UserName = “raphael.gabbarelli”
user.Password = “passwd”
user.ExpirationDate = (DateTime.Now).addYears(1)

...or you can read an existing user in the database...

user.Read(15, connection, transaction)

...and then modify it...

user.ExpirationDate = new DateTime(2008, 10, 31)

...once you need to make it persistant...

Dim id as Integer = user.Write(connection, transaction)

...Write will return in Integer >= 1 if the whole writing has gone well, -1 if there were some problems!
To write an entity on the database, you always use Write, both if it's a new entity or an existing one reda from the database.

Calling Delete you can remove it from the database...

Dim result as Boolean = user.Delete(connection, transaction)

result will be true if the whole deleting has gone well.

Many times you'll need to execute a query on the table to obtain a list of entities, in this case you can use the ReadMany method...

Dim loader As New User()
Dim params() As New Sq1Parameters(){ New SqlParameter(“@UserName”, “raphael.gabbarelli” }
Dim lista As New EntityList = loader.ReadMany(“UserName = @UserName”, params, connection, transaction)

ReadMany needs the “where condition” of a SQL statement, and an array of parameters. If you don't have a where condition, you can call ReadMany this way :

Dim lista As New EntityList = loader.ReadMany(“”, Nothing, connection, transaction)

EntityList is a collection of entities. It implements IList, so it can be used as a traditional collection
Elements in a EntityList are RecordBase, so you need to cast those object into the right type (the type of the loader).

Relations

Usually tables are related between them. An entity class models those relations in 2 ways :
in a 1...n relation, if the class is in the “n” side of the relation, the relation will be shown as a function returning an entity (the type will be the type of the “1” side of the relation).
If the class is on the “1” side of the relation, you'll see a function returning an EntityList.

e.g.

Dim user As New User()
user.Read(18, connection)
Dim profiles As EntityList = user.Profiles(connection)

Dim firstProfile As Profile = CType(profiles(0), Profile)
Dim relatedUser As User = firstProfile.User(connection)

Probably you'll have to override some methods such as Write or Delete, in this case I think it would be a good idea to override Write and Delete. Why?
Because il User and Profile are related 1...n profiles won't make sense without a user, so if I delete a user, I would be able to delete all profiles related to this user.

The first bug has just been closed!

2006-10-04T17:54:00.000+02:00

A bug was affecting the Write method called on a new entity.
In the previous version, if any field of a new entity is Nothing, the Insert method (it's a private method called by Write) will generate SqlParameters with a Nothing value.
A SqlParameter could't accept a Nothing value, instead of it we have to use a System.DbNull.Value object.
In this new version, if the value of an entity is Nothing, the SqlParameter will contains a System.DbNull.Value value.

Thanks to Ermanno Piergiacomi (Italy)

BusinessLayer Builder HOW TO

2006-10-03T17:23:00.000+02:00

How does it work?
BLB is a code generator that creates entity classes usefull to interact with the database of the application.
The first step is : design the database.
There are 2 constraints: the first is about the primary key that must be called ID, Integer, identity from 1 to x, the second constraint is about the timestamp of the record. At this time BLB contains some Italian words..so you must have a field called DataModifica, DateTime. This field name is going to be changed in UpdateTime.
If the database contains also Foreign keys the code generator will also generate functions usefull to navigate relations.
The second step is : run the application!
Define the connection parameters, press “Connect”, and you'll be connected to the database if parameters are good, if not you will see some messages in the “System error” text area.
The third step : select namespace, output folder and tables.
Once you are connected to the database, you will se a list of tables in the checkbox list. You can chose those tables wich interests you. You have to define both namespace and output folder. The first is the .NET namespace you want to assign to classes, the output folder is the folder in wich classes files will be generated.
The final step : generate classes.
Classes are ready to be generated in the output folder! If there are alredy files with the same name, BLB will delete old files and generate the new ones. In thi step the code generator will also generate one stored procedure for each selected table, if there is already a procedure, the old one will be dropped and a new one is going to take it's place.

To use those classes in your VB.NET project, you have to insert in the project also the tree classes included in the folder “basi” (the name is going to be changed into “base”).

Now you can use your entity classes!

I'm going to write a "Entities HOW-TO", it'll be available as soon as possible!

Released the translated GUI

2006-10-03T16:49:00.000+02:00

The Graphical User Interface now is in English.
As soon as possible, the source code will be in English too!
I'm still working on the road map and on technical documents.

Working on this BLOG

2006-10-03T09:00:00.000+02:00

This blog is ok just in Firefox, using Internet Exploder you may have some missing chars!!!
So at the moment I'm working to make this blog better!
I'm going to release it today (Italian business day).

The first release

2006-10-02T12:25:00.000+02:00

The first release of BusinessLayer Builder is on-line!
But what is "BusinessLayer Builder"?
BusinessLayer Builder (BLB) is a .NET (at the moment) code generator who generates VB.NET classes (at the moment!) coding the "Entities" of the project. The first step, building an application (a bancking one e.g.), is designing the database. If you want to write a good Object oriented code you should have classes to interact with the database without accessing directly to it.

Writing entity classes is boring, repetitive, and maybe a lot of errors can occour while "copying and pasting" code!!!

BLB does it for you! You design the database, BLB generates the code!