XPQueryExtensions.FirstOrDefaultAsync<T>(IQueryable<T>, Expression<Func<T, Boolean>>, CancellationToken) Method

Asynchronously gets the first object that meets specified requirements in a selection. If the selection is empty, returns a default value for <T>.

Namespace: DevExpress.Xpo

Assembly: DevExpress.Xpo.v24.1.dll

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

NuGet Package: DevExpress.Xpo

Declaration

C#

public static Task<T> FirstOrDefaultAsync<T>(
    this IQueryable<T> query,
    Expression<Func<T, bool>> predicate,
    CancellationToken cancellationToken = default(CancellationToken)
)

VB.NET

<ExtensionAttribute>
Public Shared Function FirstOrDefaultAsync(Of T)(
    query As IQueryable(Of T),
    predicate As Expression(Of Func(Of T, Boolean)),
    cancellationToken As CancellationToken = Nothing
) As Task(Of T)

Parameters

Name	Type	Description
query	IQueryable<T>	An XPQuery<T> that specifies a selection of persistent objects.
predicate	Expression<Func<T, Boolean>>	An expression which determines requirements the persistent object needs to meet.

Optional Parameters

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

Type Parameters

Name
T

Returns

Type	Description
Task<T>	A Task that returns the first object to meet specified requirements in a selection or a default value for <T>.