IAggregateFluentExtensionsFirstOrDefaultTResult Method |
Returns the first document of the aggregate result, or the default value if the result set is empty.
Namespace:
MongoDB.Driver
Assembly:
MongoDB.Driver (in MongoDB.Driver.dll) Version: 2.21.0+5a9c3311e158910b88195f290e6d4b1b2715d2b2
Syntax public static TResult FirstOrDefault<TResult>(
this IAggregateFluent<TResult> aggregate,
CancellationToken cancellationToken = null
)
<ExtensionAttribute>
Public Shared Function FirstOrDefault(Of TResult) (
aggregate As IAggregateFluent(Of TResult),
Optional cancellationToken As CancellationToken = Nothing
) As TResult
[<ExtensionAttribute>]
static member FirstOrDefault :
aggregate : IAggregateFluent<'TResult> *
?cancellationToken : CancellationToken
(* Defaults:
let _cancellationToken = defaultArg cancellationToken null
*)
-> 'TResult
Parameters
- aggregate
- Type: MongoDB.DriverIAggregateFluentTResult
The aggregate. - cancellationToken (Optional)
- Type: System.ThreadingCancellationToken
The cancellation token.
Type Parameters
- TResult
- The type of the result.
Return Value
Type:
TResult
The fluent aggregate interface.
Usage Note
In Visual Basic and C#, you can call this method as an instance method on any object of type
IAggregateFluentTResult. 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