如何将 UUID 转换为 base64，反之亦然

Question

我有以下扩展来将 UUID 转换为 base64 url 安全字符串，反之亦然。我正在努力解决 base64UrlSafeString 不返回 utf8 字符串的问题，因为底层数据是一个 UInt8 数组。至少我认为这是问题所在，因为 decodeBase64UrlSafeString() returns 的最后一行为零。有没有一种安全的方法可以将 UUID 中的 16 个字节转换为具有 utf8 编码的 Data 对象？

let uuid = UUID(uuidString: "9823c260-4feb-11e9-990c-354fb53401ce")!
print(uuid.base64UrlSafeString) //mCPCYE_rEemZDDVPtTQBzg
print(UUID.decodeBase64UrlSafeString(uuid.base64UrlSafeString)) //nil

UUID 扩展：

extension UUID {
    var base64UrlSafeString: String {
        var result = self.data.base64EncodedString()
        result = result.replacingOccurrences(of: "+", with: "-")
        result = result.replacingOccurrences(of: "/", with: "_")
        result = result.replacingOccurrences(of: "=", with: "")
        return result
    }
    var data: Data {
        var result = Data()
        result.append(uuid.0)
        result.append(uuid.1)
        result.append(uuid.2)
        result.append(uuid.3)
        result.append(uuid.4)
        result.append(uuid.5)
        result.append(uuid.6)
        result.append(uuid.7)
        result.append(uuid.8)
        result.append(uuid.9)
        result.append(uuid.10)
        result.append(uuid.11)
        result.append(uuid.12)
        result.append(uuid.13)
        result.append(uuid.14)
        result.append(uuid.15)
        return result
    }
    static func decodeBase64UrlSafeString(_ base_64_uuid: String ) -> String? {
        var base_64_uuid = base_64_uuid
        base_64_uuid = base_64_uuid.replacingOccurrences(of: "-", with: "+")
        base_64_uuid = base_64_uuid.replacingOccurrences(of: "_", with: "/")
        while base_64_uuid.count % 4 != 0 {
            base_64_uuid = base_64_uuid.appending("=")
        }
        guard let data = Data(base64Encoded: base_64_uuid) else { return nil }
        print("Got here") //code makes it here
        return String(data: data, encoding: .utf8) //returns nil!
    }
}

Answer 1

UUID 数据不是有效的 utf8 编码字符串。您需要的是将数据转换为 UUID，然后 return uuidString:

static func decodeBase64UrlSafeString(_ base_64_uuid: String) -> String? {
    var base_64_uuid = base_64_uuid
        .replacingOccurrences(of: "-", with: "+")
        .replacingOccurrences(of: "_", with: "/")
    while base_64_uuid.count % 4 != 0 { base_64_uuid += "=" }
    guard let data = Data(base64Encoded: base_64_uuid), data.count == 16 else { return nil }
    let uuid = data.withUnsafeBytes { [=10=].load(as: UUID.self) }
    return uuid.uuidString
}

如何将 UUID 转换为 base64，反之亦然

How to convert UUID to base 64 and vise versa

uuid

base64

utf-8

swift