IObjectSpace Interface
Declares members implemented by Object Space.
Namespace: DevExpress.ExpressApp
Assembly: DevExpress.ExpressApp.v23.2.dll
NuGet Package: DevExpress.ExpressApp
Declaration
Related API Members
The following members return IObjectSpace objects:
Remarks
For more information on the Object Space concept, refer to the following class description: BaseObjectSpace.
Follow the steps below to implement a custom Object Space:
- Create a new BaseObjectSpace descendant. BaseObjectSpace implements the IObjectSpace members that are not related to the data layer.
- Override BaseObjectSpace‘s protected virtual methods you want to customize.
- Implement the IObjectSpace members related to the data layer.
You can also inherit one of the BaseObjectSpace descendants.
The following article demonstrates how to create a custom Object Space class and register the custom Object Space Provider for it: How to customize the Object Space behavior in XPO-based XAF applications.
The following example demonstrates how to use the IObjectSpace methods:
using DevExpress.Data.Filtering;
using DevExpress.ExpressApp;
using DevExpress.Persistent.BaseImpl;
using System;
using System.Collections.Generic;
using System.Linq;
//...
public void MethodInsideController(IObjectSpace objectSpace) {
// In a ViewController, you can use the View.ObjectSpace property to access the current Object Space
// or call the Application.CreateObjectSpace method to create a new Object Space.
Person person = objectSpace.FirstOrDefault<Person>(p => p.FirstName == "John" && p.LastName == "Doe");
if(person != null) {
// IList<Task> outdatedTasks = objectSpace.GetObjects<Task>(CriteriaOperator.Parse("DueDate < ?", DateTime.Now));
IQueryable<Task> outdatedTasks = objectSpace.GetObjectsQuery<Task>().Where(t => t.DueDate < DateTime.Now);
foreach(Task task in outdatedTasks) {
task.AssignedTo = person;
}
}
objectSpace.CommitChanges();
}
//...
For more information on ways to access an Object Space in different scenarios, refer to the following help topic: Ways to Access an Object Space (the Database Context for CRUD Operations). To learn about Object Space API, see Create, Read, Update and Delete Data.