ヘキサ文字列からData型への変換メモ
Dataクラスを拡張してイニシャライザを追加
extension UnicodeScalar {
var hexNibble:UInt8 {
let value = self.value
if 48 <= value && value <= 57 {
return UInt8(value - 48)
}
else if 65 <= value && value <= 70 {
return UInt8(value - 55)
}
else if 97 <= value && value <= 102 {
return UInt8(value - 87)
}
fatalError("\(self) not a legal hex nibble")
}
}
extension Data {
init(hex:String) {
let scalars = hex.unicodeScalars
var bytes = Array<UInt8>(repeating: 0, count: (scalars.count + 1) >> 1)
for (index, scalar) in scalars.enumerated() {
var nibble = scalar.hexNibble
if index & 1 == 0 {
nibble <<= 4
}
bytes[index >> 1] |= nibble
}
self = Data(bytes: bytes)
}
}
エントリポイントにて
let data:Data = Data( hex:"3c91d3c062df9caa79b4b2353c12a1295512987200002")