EntitySpaces

 

Download:
EntitySpaces 2008.1.0922.0(200809/22):

 

 

Persistence Layer and Business Objects for Microsoft .NET  

EntitySpaces 2008.1.0922.0 (maintenance release) was released on September 22nd, 2008. 

Example Source

Features:

  • Mono Support
  • Compact Framework Support
  • Medium Trust Support
  • Design Time Data Binding
  • Hierarchical Data Models
  • Powerful Dynamic Query API
  • Binary and XML Serialization
  • CodeSmith and MyGeneration Support
  • Data Provider Independence
  • Two Different Transaction Models
  • Saving via Stored Procedures or Dynamic SQL
  • Generated from your Database Schema
  • No XML mapping files. 
  • LINQ Support for Collections 
  • Regenerate Without Losing Custom Business Logic
  • Admin Grid Template Suite for ASP.NET
  • Admin Grid Template Suite for DotNetNuke
  • Source Code Available


Providers Available:

  • Microsoft SQL Server / SQL CE
  • Microsoft Access
  • Oracle
  • MySQL
  • VistaDB 
  • PostgreSQL

   

EntitySpaces on .NET Rocks
Mike Griffin, of EntitySpaces, talks with Carl and Richard about EntitySpaces, a persistence layer and business object system for the Microsoft .NET 2.0 Framework, as well as his experiences with LINQ and other technologies.

 

From mobile devices to large scale enterprise solutions in need of serious transaction support, EntitySpaces is the development tool that can meet your needs. Whether you’re writing an ASP.NET application with medium trust requirements, or a Windows.Forms application, the EntitySpaces architecture is there for you. EntitySpaces is provider independent, which means that you can run the same binary code against any of the supported databases. EntitySpaces is available in both C# and VB.NET. EntitySpaces uses no reflection, no xml files, and sports a tiny foot print of less than 200k. Pound for pound, EntitySpaces is one tough .NET architecture.

Although EntitySpaces targets both ASP.NET and Windows.Forms projects, DotNetNuke module developers will find EntitySpaces to be an attractive alternative to the DotNetNuke DAL. Many of the features listed above, including important ones like transactions, are not available when using the DotNetNuke DAL API. The EntitySpaces provider independence model we feel is much easier because it is basically transparent and provided by EntitySpaces itself. It is not left up to you, the developer, to create. EntitySpaces handles it for you. There is a sample DotNetNuke module on our main menu, take a look at the source code listing too.

EntitySpaces Goes Mobile
The EntitySpaces team decided to take a slight detour from its upcoming 1.6.0 release and add support for the Compact Framework to its popular architecture, which is a persistence layer and business object system for Microsoft .NET 2.0. Support for the Compact Framework paves the way for VistaDB 3.0 and the Microsoft SQL Compact Edition well in advance of their official releases. Both VistaDB 3.0 and the Microsoft SQL Compact Edition are still in CTP mode. EntitySpaces classes are generated from your database schema using download.com's #1 download in the .NET development category, MyGeneration, using the EntitySpaces template suite.

 

EntitySpaces LLC has created a sample application using a very powerful combination of its EntitySpaces architecture in conjunction with VistaDB 3.0, and running both under the Windows Mobile 5.0 Smartphone emulator. Setting up the demo solution was very simple. First, references to the EntitySpaces.Core.Ce and EntitySpaces.Interfaces.Ce assemblies were added. Next, a reference to the EntitySpaces.VistaDB.Ce data provider was added. Finally, the VistaDB Northwind.vdb3 database was added to the project and its "Build Action" was set to "Content" to ensure that the database is copied along with the other assemblies to the proper folder when the simulator is launched. To see the solution in Visual Studio

.


Click here for a larger view The next step was to write the code to connect to the VistaDB Northwind database. To accomplish this, the new configless execution feature provided by the recent EntitySpaces 1.5.2 release was used. The trick was actually figuring out how to get the correct path to the database while running in the simulator. You can see how this was accomplished in the first line of the following code snippet.

    string cnString = ("Data Source =" + (System.IO.Path.GetDirectoryName
(System.Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase) +
"\\Northwind.vdb3; Open Mode = ExclusiveReadWrite"));
// What the heck let's register a connection
esConnectionElement conn = new esConnectionElement();
conn.ConnectionString = cnString;
conn.Name = "VistaDb";
conn.Provider = "EntitySpaces.VistaDBProvider.Ce";
conn.ProviderClass = "DataProvider";
conn.SqlAccessType = esSqlAccessType.DynamicSQL;
conn.ProviderMetadataKey = "esDefault";
esConfigSettings.ConnectionInfo.Connections.Add(conn);
// Assign the Default Connection
esConfigSettings.ConnectionInfo.Default = "VistaDb";


The only option on the opening Menu brings the user to a form which contains a DataGrid bound directly to an EntitySpaces EmployeesCollection object loaded with all of the employees in the database. Note that you can use the EntitySpaces collections in design time mode directly on the form itself. The EntitySpaces dynamic query mechanism was used to limit the columns brought back from the database to only those needed to operate the DataGrid. These included the EmployeeID, FirstName, and LastName columns. Finally, the DataGrid TableStyles collection was used to set the EmployeeID column's width to zero so that it would not be visible. The only thing left to do is fetch the data and assign the EntitySpaces collection directly to the DataGrid.DataSource property.

The developer will never need to use any ADO.NET code, or any specific VistaDB code to accomplish this task. In fact, the developer could easily swap out the EntitySpaces VistaDB provider and exchange it for the EntitySpaces Microsoft SQL CE provider, and run the same exact binary code. The EntitySpaces architecture itself is tested using NUnit against all five supported databases using the same exact binary code. No recompilation necessary. The code used to fetch the data and bind to the DataGrid is shown below and taken from the FormGrid class in the demo.

 

Click here for a larger view     private void PopulateGrid()
{
EmployeesCollection empColl = new EmployeesCollection();
empColl.Query.Select
(
empColl.Query.EmployeeID,
empColl.Query.FirstName,
empColl.Query.LastName
);
empColl.Query.Load();
this.theGrid.DataSource = empColl;
}

It really is that simple. Next, the "Edit Record" menu item needs to be handled in order to navigate to the editing form. To accomplish this the hidden EmployeeID needs to be grabbed, and passed to the "FormEdit" page based on the selected row at the time the "Edit Record" menu item is clicked.

 
    private void menuItem_EditRecord_Click(object sender, EventArgs e)
{
int index = this.theGrid.CurrentRowIndex;
int id = (int)this.theGrid[index, 0];  // index is the row
                                               // zero = the first column
FormEdit form = new FormEdit(id);
form.Show();
}

It is on the editing page where users can modify, delete, and add new records. Remember from above that the EmployeeID is passed to the FormEdit page. The constructor for the FormEdit page is very easy to implement using EntitySpaces architecture. Here, instead of the EmployeesCollection, the Employees class is used to load the correct record. The Employees class is used to hold a single record, whereas, the EmployeesCollection holds a set of Employees classes. The record is loaded using the LoadByPimaryKey method as shown in the code snippet below. Finally, the labels and textbox controls are populated with the data from the EntitySpaces Employees object. 


 

Click here for a larger view

 

 

    public FormEdit(int employeeID)
{
InitializeComponent();
Employees emp = new Employees();
if (emp.LoadByPrimaryKey(employeeID))
{
this.lblID.Text = emp.str.EmployeeID;
this.txtFirstName.Text = emp.FirstName;
this.txtLastName.Text  = emp.LastName;
}
else
{
this.lblError.Text = "Employee not found";
}
}

On the editing screen shown on the left Margaret's first name has been changed to "Mary" and then saved using Save on the menu. The ability to add and delete records is in the EntitySpaces Mobile demo too but not shown here. Pressing close will return the user to the DataGrid form reflecting any edits that may have occurred. The image on the right reveals that not only was Margaret's name changed to Mary, but "Mike Griffin" was added to the database as well. The grid is refreshed in the Activated event of the FormGrid class. 

It should be clearly seen how easy EntitySpaces can be used to work with the Compact Framework. Click here for a larger viewWhile creating the demo we were very impressed with VistaDB 3.0. VistaDB has some features that we found make it very attractive. First, VistaDB has some nice advantages over the Microsoft SQL Compact Edition. The VistaDB Namespace doesn't change when moving to the Compact Framework. The Microsoft Compact Edition, however, uses SqlCeClient instead of SqlClient, which makes it more difficult for developers to maintain a single codebase. The EntitySpaces architecture conveniently hides these low level issues from the developer, thereby isolating code from such provider quirks. Also, the same VistaDB database (the exact same physical file) will run on all environments with no loss of features or a lesser SQL syntax when running under the Compact Framework.

Having said that, the EntitySpaces Architecture does support the Microsoft SQL Compact Edition fully, and we will publishing the same demo application shown here for it very soon. We are just putting a few finishing touches on the EntitySpaces provider for the Microsoft SQL Compact Edition. The SQL supported under the Microsoft SQL Compact Edition is different than what is allowable under Microsoft SQL 2005. The EntitySpaces user of course will never realize these differences and that is one of the main strengths of EntitySpaces.

The EntitySpaces Mobile demo will be available for download Monday December 4th by 8:00 AM EST time. A link will be posted on this page.

 

 

 

 

 

 

 

 

下载地址:http://www.fosoyo.com/article.asp?id=138

 

posted on 2008-10-01 15:37  fosoyo  阅读(885)  评论(0编辑  收藏  举报