Encryption and Decryption in Salesforce

Blob key = Crypto.generateAesKey(128);

string keyvalue=EncodingUtil.base64Encode(key);

Blob data = Blob.valueOf('Data to be encrypted');

Blob encrypted = Crypto.encryptWithManagedIV('AES128', key, data);

string dataval=EncodingUtil.base64Encode(encrypted);

system.debug('***key***'+keyvalue);

system.debug('****data***'+dataval);

Blob decrypted = Crypto.decryptWithManagedIV('AES128', key, encrypted);

String decryptedString = decrypted.toString();

System.assertEquals('Data to be encrypted', decryptedString);