在Swift 5中获取字符串md5

import CommonCrypto

extension String {
    var md5: String {
        if let data = self.data(using: .utf8) {
            var digest = [UInt8](repeating: 0, count: Int(CC_MD5_DIGEST_LENGTH))
            _ = data.withUnsafeBytes { bytes in
                CC_MD5(bytes.baseAddress, CC_LONG(data.count), &digest)
            }
            
            var md5String = ""
            for byte in digest {
                md5String += String(format: "%02x", byte)
            }
            
            return md5String
        }
        
        return ""
    }
}

let str = "Hello, world!"
let md5Value = str.md5
print(md5Value)