MongoQueryableSumAsyncTSource Method (IMongoQueryableTSource, ExpressionFuncTSource, NullableInt64, CancellationToken) |
Computes the sum of the sequence of
NullableT values that is obtained
by invoking a projection function on each element of the input sequence.
Namespace:
MongoDB.Driver.Linq
Assembly:
MongoDB.Driver (in MongoDB.Driver.dll) Version: 2.22.0+75246110ed1247226fcc7f8eb2c54ffab745693e
Syntax public static Task<long?> SumAsync<TSource>(
this IMongoQueryable<TSource> source,
Expression<Func<TSource, long?>> selector,
CancellationToken cancellationToken = default
)
<ExtensionAttribute>
Public Shared Function SumAsync(Of TSource) (
source As IMongoQueryable(Of TSource),
selector As Expression(Of Func(Of TSource, Long?)),
Optional cancellationToken As CancellationToken = Nothing
) As Task(Of Long?)
[<ExtensionAttribute>]
static member SumAsync :
source : IMongoQueryable<'TSource> *
selector : Expression<Func<'TSource, Nullable<int64>>> *
?cancellationToken : CancellationToken
(* Defaults:
let _cancellationToken = defaultArg cancellationToken new CancellationToken()
*)
-> Task<Nullable<int64>>
Parameters
- source
- Type: MongoDB.Driver.LinqIMongoQueryableTSource
A sequence of values. - selector
- Type: System.Linq.ExpressionsExpressionFuncTSource, NullableInt64
A projection function to apply to each element. - cancellationToken (Optional)
- Type: System.ThreadingCancellationToken
The cancellation token.
Type Parameters
- TSource
- The type of the elements of source.
Return Value
Type:
TaskNullableInt64
The sum of the projected values.
Usage Note
In Visual Basic and C#, you can call this method as an instance method on any object of type
IMongoQueryableTSource. 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