QueryBuilder.SumByNullable<'T,'Q,^Value> Method (F#)

  • Article

A query operator that selects a nullable value for each element selected so far and returns the sum of these values. If any nullable element does not have a value, it is ignored.

Namespace/Module Path: Microsoft.FSharp.Linq

Assembly: FSharp.Core (in FSharp.Core.dll)

// Signature:
member this.SumByNullable : QuerySource<'T,'Q> * ('T -> Nullable<^Value>) -> Nullable<^Value> when ^Value with static member (+) and ^Value with static member Zero and ^Value : (new : unit ->  ^Value) and ^Value : struct and ^Value :> ValueType

// Usage:
queryBuilder.SumByNullable (source, valueSelector)

Parameters

  • source
    Type: QuerySource<'T,'Q>

    The input query.

  • valueSelector
    Type: 'T -> Nullable<^Value>

    A function to compute the values to sum.

Return Value

The resulting sum.

Remarks

For more information and examples, see Query Expressions (F#).

Platforms

Windows 8, Windows 7, Windows Server 2012, Windows Server 2008 R2

Version Information

F# Core Library Versions

Supported in: 4.0, Portable

See Also

Reference

Linq.QueryBuilder Class (F#)

Microsoft.FSharp.Linq Namespace (F#)

Query Expressions (F#)