AES 256 Symmetric Cryptography

I am unable to encrypt or decrypt using aes 256 block mode cbc padding pkcs5

please convert this c# to swift

````public class EncDec
{

       static string key = ""; // your key
       public static string Encrypt(string data)
        {
            RijndaelManaged rijndaelCipher = new RijndaelManaged();
            rijndaelCipher.Mode = CipherMode.CBC; //remember this parameter
            rijndaelCipher.Padding = PaddingMode.PKCS7; //remember this parameter

            rijndaelCipher.KeySize = 0x80;
            rijndaelCipher.BlockSize = 0x80;
            byte[] pwdBytes = Encoding.UTF8.GetBytes(key);
            byte[] keyBytes = new byte[0x10];
            int len = pwdBytes.Length;

            if (len > keyBytes.Length)
            {
                len = keyBytes.Length;
            }

            Array.Copy(pwdBytes, keyBytes, len);
            rijndaelCipher.Key = keyBytes;
            rijndaelCipher.IV = keyBytes;
            ICryptoTransform transform = rijndaelCipher.CreateEncryptor();
            byte[] plainText = Encoding.UTF8.GetBytes(data);

            return Convert.ToBase64String
            (transform.TransformFinalBlock(plainText, 0, plainText.Length));
        }

        public static string Decrypt(string data)
        {
            if (data != null)
            {
                RijndaelManaged rijndaelCipher = new RijndaelManaged();
                rijndaelCipher.Mode = CipherMode.CBC;
                rijndaelCipher.Padding = PaddingMode.PKCS7;

                rijndaelCipher.KeySize = 0x80;
                rijndaelCipher.BlockSize = 0x80;
                byte[] encryptedData = Convert.FromBase64String(data);
                byte[] pwdBytes = Encoding.UTF8.GetBytes(key);
                byte[] keyBytes = new byte[0x10];
                int len = pwdBytes.Length;

                if (len > keyBytes.Length)
                {
                    len = keyBytes.Length;
                }

                Array.Copy(pwdBytes, keyBytes, len);
                rijndaelCipher.Key = keyBytes;
                rijndaelCipher.IV = keyBytes;
                byte[] plainText = rijndaelCipher.CreateDecryptor().TransformFinalBlock
                            (encryptedData, 0, encryptedData.Length);

                return Encoding.UTF8.GetString(plainText);
            }
            else
            {
                return null;
            }

        }
    }````