IAsyncCursorExtensionsFirstOrDefaultAsyncTDocument Method |
Returns the first document of the cursor, or a default value if the cursor contains no documents.
Namespace:
MongoDB.Driver
Assembly:
MongoDB.Driver.Core (in MongoDB.Driver.Core.dll) Version: 2.7.3+Branch.v2.7.x.Sha.2f1f2be13a23b8520cb9c2ee8439c022f9a03efe
Syntax public static Task<TDocument> FirstOrDefaultAsync<TDocument>(
this IAsyncCursor<TDocument> cursor,
CancellationToken cancellationToken = null
)
<ExtensionAttribute>
Public Shared Function FirstOrDefaultAsync(Of TDocument) (
cursor As IAsyncCursor(Of TDocument),
Optional cancellationToken As CancellationToken = Nothing
) As Task(Of TDocument)
[<ExtensionAttribute>]
static member FirstOrDefaultAsync :
cursor : IAsyncCursor<'TDocument> *
?cancellationToken : CancellationToken
(* Defaults:
let _cancellationToken = defaultArg cancellationToken null
*)
-> Task<'TDocument>
Parameters
- cursor
- Type: MongoDB.DriverIAsyncCursorTDocument
The cursor. - cancellationToken (Optional)
- Type: System.ThreadingCancellationToken
The cancellation token.
Type Parameters
- TDocument
- The type of the document.
Return Value
Type:
TaskTDocumentA task whose result is the first document of the cursor, or a default value if the cursor contains no documents.
Usage Note
In Visual Basic and C#, you can call this method as an instance method on any object of type
IAsyncCursorTDocument. When you use instance method syntax to call this method, omit the first parameter. For more information, see
Extension Methods (Visual Basic) or
Extension Methods (C# Programming Guide).
See Also