Access XAF Application Data in a non-XAF Application

• Jul 31, 2021
• 4 minutes to read

In certain scenarios, you may need to create an auxiliary application for database maintenance and use Object Space to query your primary XAF application data. This topic describes how you can create and use Object Space in a regular non-XAF application.

Important

We do not recommend using the approach described here in XAF applications. Instead, always use the XafApplication.CreateObjectSpace method or access an existing Object Space.

In a non-XAF application, you have no XafApplication object to create an Object Space. But, an XafApplication does not create Object Spaces itself. Internally, it uses the Object Space Provider designed to create Object Spaces for the currently used ORM and those registered in its overridden XafApplication.CreateDefaultObjectSpaceProvider method. In a non-XAF application, you can instantiate the Object Space Provider manually. Then, you can call the provider’s CreateObjectSpace method to create an Object Space.

ORM	Object Space Provider
XPO	XPObjectSpaceProvider / SecuredObjectSpaceProvider
Entity Framework 6	EFObjectSpaceProvider / SecuredObjectSpaceProvider
Entity Framework Core	EFCoreObjectSpaceProvider / SecuredEFCoreObjectSpaceProvider

Note

If you want to use the Security System in your non-XAF application, refer to the following help topic: Use the Security (Access Control & Authentication) API in Non-XAF Applications - Free Offer.

XPO Example

In XPO-based applications, you should initialize the Types Info Subsystem. The following example demonstrates how to access data of the MainDemo application (typically installed to %PUBLIC%\Documents\DevExpress Demos 21.2\Components\eXpressApp Framework\MainDemo) and write the list of Departments to the standard output stream:

C#

using DevExpress.ExpressApp.Xpo;
using DevExpress.ExpressApp;
using MainDemo.Module.BusinessObjects;
// ...
class Program {
    static void Main(string[] args) {
        XpoTypesInfoHelper.GetXpoTypeInfoSource();
        XafTypesInfo.Instance.RegisterEntity(typeof(Department));
        XPObjectSpaceProvider osProvider = new XPObjectSpaceProvider(
        @"integrated security=SSPI;pooling=false;data source=(localdb)\v11.0;initial catalog=MainDemo_", null);
        IObjectSpace objectSpace = osProvider.CreateObjectSpace();
        foreach (Department department in objectSpace.GetObjects<Department>()) {
            Console.WriteLine(department.Title + "\t" + department.Office);
        }
    }
}

VB.NET

Imports Microsoft.VisualBasic
Imports DevExpress.ExpressApp.Xpo
Imports DevExpress.ExpressApp
Imports MainDemo.Module.BusinessObjects
' ...
Friend Class Program
    Shared Sub Main(ByVal args() As String)
        XpoTypesInfoHelper.GetXpoTypeInfoSource()
        XafTypesInfo.Instance.RegisterEntity(GetType(Department))
        Dim osProvider As New XPObjectSpaceProvider("integrated security=SSPI;pooling=false;data source=(localdb)\v11.0;initial catalog=MainDemo_", Nothing)
        Dim objectSpace As IObjectSpace = osProvider.CreateObjectSpace()
        For Each department As Department In objectSpace.GetObjects(Of Department)()
            Console.WriteLine(department.Title & vbTab & department.Office)
        Next department
    End Sub
End Class

Entity Framework 6 Example

You can use the following code to access data of the EFDemo application (typically installed to %PUBLIC%\Documents\DevExpress Demos 21.2\Components\eXpressApp Framework\EFDemoCodeFirst) and write the list of Departments to the standard output stream.

C#

using DevExpress.ExpressApp.EF;
using DevExpress.ExpressApp;
using EFDemo.Module.Data;
// ...
class Program {
    static void Main(string[] args) {
        EFObjectSpaceProvider osProvider = new EFObjectSpaceProvider(typeof(EFDemoDbContext),
            "integrated security=True;multipleactiveresultsets=True;data source=(localdb)\\v11.0;initial catalog=EFDemo_");
        XafTypesInfo.Instance.RegisterEntity(typeof(Department));
        IObjectSpace objectSpace = osProvider.CreateObjectSpace();
        foreach (Department department in objectSpace.GetObjects<Department>()) {
           Console.WriteLine(department.Title + "\t" + department.Office);
        }
    }
}

VB.NET

Imports DevExpress.ExpressApp.EF
Imports DevExpress.ExpressApp
Imports EFDemo.Module.Data
' ...
Friend Class Program
    Shared Sub Main(ByVal args() As String)
        Dim osProvider As New EFObjectSpaceProvider(GetType(EFDemoDbContext), _
        "integrated security=True;pooling=false;multipleactiveresultsets=True;data source=(localdb)\v11.0;initial catalog=EFDemo_")
        XafTypesInfo.Instance.RegisterEntity(GetType(Department))
        Dim objectSpace As IObjectSpace = osProvider.CreateObjectSpace()
        For Each department As Department In objectSpace.GetObjects(Of Department)()
            Console.WriteLine(department.Title & vbTab & department.Office)
        Next department
    End Sub
End Class

Entity Framework Core Example

You can use the following code to access data of the EFCore console or WinForms application (demonstrated in this repository) and write the list of Departments to the standard output stream.

C#

using DevExpress.ExpressApp;
using DevExpress.ExpressApp.EFCore;
using Microsoft.EntityFrameworkCore;
using System;
// ...
class Program {
    static void Main() {
        EFCoreObjectSpaceProvider objectSpaceProvider = new EFCoreObjectSpaceProvider(typeof(ApplicationDbContext),
            (builder, _) => builder.UseSqlServer(
                "Data Source=(localdb)\\MSSQLLocalDB;Initial Catalog=EFCoreTestDB;Integrated Security=True;MultipleActiveResultSets=True"));
        XafTypesInfo.Instance.RegisterEntity(typeof(Department));
        IObjectSpace objectSpace = objectSpaceProvider.CreateObjectSpace();
        foreach (Department department in objectSpace.GetObjects<Department>()) {
            Console.WriteLine(department.Title + "\t" + department.Office);
        }
    }
}

Note

If you need to populate the database with initial data, use the DatabaseUpdater.Update method as follows:

C#

using DevExpress.ExpressApp.Updating;
// ...
DatabaseUpdater databaseUpdater = new DatabaseUpdater(
    osProvider, new ModuleBase[0], "", osProvider.ModuleInfoType);
databaseUpdater.Update();

VB.NET

Imports DevExpress.ExpressApp.Updating
' ...
Dim databaseUpdater As New DatabaseUpdater( _
osProvider, New ModuleBase(){}, "", osProvider.ModuleInfoType)
databaseUpdater.Update()