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Map.TryFind<'Key,'Value> Method (F#)

  • Artykuł

Lookup an element in the map, returning a Some value if the element is in the domain of the map and None if not.

Namespace/Module Path: Microsoft.FSharp.Collections

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

// Signature:
member this.TryFind : 'Key -> 'Value option (requires comparison)

// Usage:
map.TryFind (key)

Parameters

  • key
    Type: 'Key

    The input key.

Return Value

The mapped value, or None if the key is not in the map.

Example

The following code shows how to use the TryFind method.

let map1 = [ for i in 1 .. 100 -> (i, i*i) ] |> Map.ofList
let result = map1.TryFind 50
match result with
| Some x -> printfn "Found %d." x
| None -> printfn "Did not find the specified value."

Output

Found 2500.

Platforms

Windows 7, Windows Vista SP2, Windows XP SP3, Windows XP x64 SP2, Windows Server 2008 R2, Windows Server 2008 SP2, Windows Server 2003 SP2

Version Information

F# Runtime

Supported in: 2.0, 4.0

Silverlight

Supported in: 3

See Also

Reference

Collections.Map<'Key,'Value> Class (F#)

Microsoft.FSharp.Collections Namespace (F#)