当response支持持续写入时，会直接回复响应。并阻塞执行，直到完成。所以在执行该方法之前，请确保已设置完成所有状态字
当response不支持持续写入时，会填充Content，且不会响应，需要自己执行Build，并发送。
public static Task FromFileAsync(
this HttpContext context,
FileInfo fileInfo,
string fileName = null,
int maxSpeed = 2147483647,
int bufferLen = 65536,
bool autoGzip = true
)<ExtensionAttribute>
Public Shared Function FromFileAsync (
context As HttpContext,
fileInfo As FileInfo,
Optional fileName As String = Nothing,
Optional maxSpeed As Integer = 2147483647,
Optional bufferLen As Integer = 65536,
Optional autoGzip As Boolean = true
) As Task[<ExtensionAttribute>]
static member FromFileAsync :
context : HttpContext *
fileInfo : FileInfo *
?fileName : string *
?maxSpeed : int *
?bufferLen : int *
?autoGzip : bool
(* Defaults:
let _fileName = defaultArg fileName null
let _maxSpeed = defaultArg maxSpeed 2147483647
let _bufferLen = defaultArg bufferLen 65536
let _autoGzip = defaultArg autoGzip true
*)
-> Task [缺少 "M:TouchSocket.Http.HttpExtensions.FromFileAsync(TouchSocket.Http.HttpContext,System.IO.FileInfo,System.String,System.Int32,System.Int32,System.Boolean)" 的 <returns> 文档]