IOExtensionsWriteStreamAsync - метод

public static Task WriteStreamAsync(
	this Stream source,
	Stream target,
	CancellationToken cancellationToken = default
)

<ExtensionAttribute>
Public Shared Function WriteStreamAsync ( 
	source As Stream,
	target As Stream,
	Optional cancellationToken As CancellationToken = Nothing
) As Task

public:
[ExtensionAttribute]
static Task^ WriteStreamAsync(
	Stream^ source, 
	Stream^ target, 
	CancellationToken cancellationToken = CancellationToken()
)

[<ExtensionAttribute>]
static member WriteStreamAsync : 
        source : Stream * 
        target : Stream * 
        ?cancellationToken : CancellationToken 
(* Defaults:
        let _cancellationToken = defaultArg cancellationToken new CancellationToken()
*)
-> Task