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在f#match语句中如何匹配类型byte []?

[英]in f# match statement how do I match to the type byte[]?

I'm trying to lookup DbType enumeration values from .net types. 我正在尝试从.net类型中查找DbType枚举值。 I'm using a match statement. 我正在使用match语句。 However I cannot figure out how to match on the type byte[]. 但是,我不知道如何在类型byte []上进行匹配。

let dbType x =
  match x with
  | :? Int64 -> DbType.Int64
  | :? Byte[] -> DbType.Binary // this gives an error
  | _ -> DbType.Object

If there is a better way to map these types, I would be open to suggestions. 如果有更好的方法来映射这些类型,我会提出建议。

byte[] , byte array , and array<byte> are all synonymous, but in this context only the last will work without parentheses: byte[]byte arrayarray<byte>都是同义词,但是在这种情况下,只有最后一个可以不带括号:

let dbType (x:obj) =
    match x with
    | :? (byte[])     -> DbType.Binary
    | :? (byte array) -> DbType.Binary // equivalent to above
    | :? array<byte>  -> DbType.Binary // equivalent to above
    | :? int64        -> DbType.Int64
    | _               -> DbType.Object

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