16進数文字列からDataを生成するString.Index版。たぶんさっきのと同じ結果 #CodePiece

CodePiece.swift

let hexString = "0123456789abcdefABCDEF"

var bytes = [UInt8]()
var index = hexString.startIndex

while let i = hexString.index(index, offsetBy: 2, limitedBy: hexString.endIndex) {
    let byteLiteral = hexString.substring(with: index..<i)
    guard let byte = UInt8(byteLiteral, radix: 16) else { continue }
    bytes.append(byte)
    index = i
}

Data(bytes: bytes) as NSData