1. Select the file to be encrypted.

2. Choose the encryption mode:

   • Single encryption: Use either 3DES or Blowfish.
   • Double encryption: Use 3DES first, followed by Blowfish.

3. Execute the encryption process.

Additionally, a driver-based encryption method is available, which can be toggled via a dedicated switch in the UI.

1. 3DES encryption is not compatible with Blowfish, causing problems in double encryption scenarios.
2. Appending the MD5 checksum at the end of the ciphertext is not a proper or secure method.
3. When using double encryption, the decryption order must be the reverse of the encryption order.

1. Key storage method should be updated — for example, by storing keys in a MySQL database.

2. Double encryption could be integrated into a unified encryption scheme to simplify the process.

3. Optimize code performance:

   • Improve speed through multithreading.
   • Use data segmentation to enhance encryption/decryption efficiency.