Session.FindObjectAsync(PersistentCriteriaEvaluationBehavior, XPClassInfo, CriteriaOperator, AsyncFindObjectCallback) Method
Asynchronously searches for the first object which matches the specified criteria, and notifies upon completion.
Namespace: DevExpress.Xpo
Assembly: DevExpress.Xpo.v18.2.dll
Declaration
public object FindObjectAsync(
PersistentCriteriaEvaluationBehavior criteriaEvaluationBehavior,
XPClassInfo classInfo,
CriteriaOperator criteria,
AsyncFindObjectCallback callback
)
Parameters
Name | Type | Description |
---|---|---|
criteriaEvaluationBehavior | PersistentCriteriaEvaluationBehavior | A PersistentCriteriaEvaluationBehavior enumeration value that specifies how the persistent criteria is evaluated. |
classInfo | XPClassInfo | An XPClassInfo object which contains the metadata information of the class. |
criteria | CriteriaOperator | A CriteriaOperator descendant which represents the criteria to match persistent objects. |
callback | DevExpress.Xpo.Helpers.AsyncFindObjectCallback | A DevExpress.Xpo.Helpers.AsyncFindObjectCallback delegate to be called after the method completes. Use callback to do the following:
Do not raise exceptions or modify persistent objects within a callback. |
Returns
Type | Description |
---|---|
Object | An object which represents the first persistent object matching the specified criteria. null (Nothing in Visual Basic) if no persistent object matching the criteria is found. |
Remarks
Persistent objects that are marked as deleted in the database (see Deferred and Immediate Object Deletion) are not included in the search.