C# 实现 AES 加密算法

public enum enmKeyBit
{
    KeyBit128 = 128,
    KeyBit192 = 192,
    KeyBit256 = 256,
}

public class EncryptNew
{
    /// <summary>
    /// AES ECB模式 加密
    /// </summary>
    /// <param name="data">明文</param>
    /// <param name="key">密钥</param>
    /// <param name="keyBit">密钥位数</param>
    /// <returns></returns>
    public static string AESEncrypt(String data, String key, enmKeyBit keyBit = enmKeyBit.KeyBit256)
    {
        if (string.IsNullOrEmpty(data))
        {
            return string.Empty;
        }

        try
        {
            int intKeyBit = (int)keyBit;
            RijndaelManaged aes = new RijndaelManaged();
            byte[] bytsData = Encoding.UTF8.GetBytes(data);
            byte[] bytsKey = new Byte[intKeyBit / 8];
            Array.Copy(Encoding.UTF8.GetBytes(key.PadRight(bytsKey.Length)), bytsKey, bytsKey.Length);

            aes.Mode = CipherMode.ECB;
            aes.Padding = PaddingMode.PKCS7;
            aes.KeySize = intKeyBit;
            aes.Key = bytsKey;
            //aes.IV = iv;
            ICryptoTransform ctf = aes.CreateEncryptor();
            byte[] bytsResult = ctf.TransformFinalBlock(bytsData, 0, bytsData.Length);

            return Convert.ToBase64String(bytsResult);
        }
        catch
        {
            return string.Empty;
        }
    }

    /// <summary>
    /// AES ECB模式 解密
    /// </summary>
    /// <param name="data">密文</param>
    /// <param name="key">密钥</param>
    /// <param name="keyBit">密钥位数</param>
    /// <returns></returns>
    public static string AESDecrypt(String data, String key, enmKeyBit keyBit = enmKeyBit.KeyBit256)
    {
        if (string.IsNullOrEmpty(data))
        {
            return string.Empty;
        }

        try
        {
            int intKeyBit = (int)keyBit;
            RijndaelManaged aes = new RijndaelManaged();
            byte[] bytsData = Convert.FromBase64String(data);
            byte[] bytsKey = new Byte[intKeyBit / 8];
            Array.Copy(Encoding.UTF8.GetBytes(key.PadRight(bytsKey.Length)), bytsKey, bytsKey.Length);

            aes.Mode = CipherMode.ECB;
            aes.Padding = PaddingMode.PKCS7;
            aes.KeySize = intKeyBit;
            aes.Key = bytsKey;
            //aes.IV = iv;

            ICryptoTransform ctf = aes.CreateDecryptor();
            byte[] bytsResult = ctf.TransformFinalBlock(bytsData, 0, bytsData.Length);

            return UTF8Encoding.UTF8.GetString(bytsResult);
        }
        catch
        {
            return string.Empty;
        }
    }
}