Session.GetObjectByKeyAsync(XPClassInfo, Object, Boolean, CancellationToken) Method

Asynchronously returns a persistent object that has the specified key property value from a data store.

Namespace: DevExpress.Xpo

Assembly: DevExpress.Xpo.v23.2.dll

NuGet Packages: DevExpress.Win.PivotGrid, DevExpress.Win.TreeMap, DevExpress.Xpo

NuGet Package: DevExpress.Xpo

Declaration

C#

public Task<object> GetObjectByKeyAsync(
    XPClassInfo classInfo,
    object id,
    bool alwaysGetFromDataStore,
    CancellationToken cancellationToken = default(CancellationToken)
)

VB.NET

Public Function GetObjectByKeyAsync(
    classInfo As XPClassInfo,
    id As Object,
    alwaysGetFromDataStore As Boolean,
    cancellationToken As CancellationToken = Nothing
) As Task(Of Object)

Parameters

Name	Type	Description
classInfo	XPClassInfo	An XPClassInfo object which contains the metadata information of the class.
id	Object	An object which represents the key property’s value of the persistent object.
alwaysGetFromDataStore	Boolean	true, to always reload the persistent object from storage even if it is found in memory; otherwise, false.

Optional Parameters

Name	Type	Default	Description
cancellationToken	CancellationToken	null	A CancellationToken object that delivers a cancellation notice to the running operation.

Returns

Type	Description
Task<Object>	A Task that returns a persistent object from a data store. This persistent object has the specified key property value. The task returns null if no objects are found.

Remarks

Below is an example of using the GetObjectByKeyAsync method. Here, the session is the Session instance.

C#

using System.Threading;
using DevExpress.Xpo;
using DevExpress.Xpo.Metadata;
// ...
XPClassInfo personClassInfo = session.GetClassInfo(typeof(Person));
CancellationTokenSource source = new CancellationTokenSource();
CancellationToken cancellationToken = source.Token;
Person personToDelete = 
    (Person)await session.GetObjectByKeyAsync(personClassInfo, 152, true, cancellationToken);
session.Delete(personToDelete);

VB.NET

Imports System.Threading
Imports DevExpress.Xpo
Imports DevExpress.Xpo.Metadata
' ...
Private personClassInfo As XPClassInfo = session.GetClassInfo(GetType(Person))
Private source As New CancellationTokenSource()
Private cancellationToken As CancellationToken = source.Token
Dim personToDelete As Person = _
    CType(Await session.GetObjectByKeyAsync(personClassInfo, 152, True, cancellationToken), Person)
session.Delete(personToDelete)

The GetObjectByKeyAsync method searches in memory for the object with the specified key property value. If such an object is found, it is not reloaded. To get the up-to-date object from storage the alwaysGetFromDataStore parameter must be set to true.