Encryption with Parameters C# SQL Server Not Saving Properly -

i trying insert encrypted data sql table. trying save 2 random numbers. here code generating random numbers:

        random randomnumber = new random();         int key1 = randomnumber.next(10000000, 99999999);         thread.sleep(1000);         random randomnumber2 = new random(datetime.now.second);         int key2 = randomnumber2.next(10000000, 99999999); 

then insert table. first set of code works can't use because doesn't work random numbers. confirm have right:

       sqlcommand cmd = new sqlcommand(@"open symmetric key keycodeskey decryption certificate keycodes;        insert keyfile(encrypted_key1, encrypted_key2, startingkeydate) values (encryptbykey(key_guid('keycodeskey'), '19630515'), encryptbykey(key_guid('keycodeskey'), '19520921'), current_timestamp)", cx);        int success = cmd.executenonquery(); 

this code prefer use can't seem work:

        sqlcommand cmd = new sqlcommand(@"open symmetric key keycodeskey decryption certificate keycodes;          insert keyfile(encrypted_key1, encrypted_key2, startingkeydate) values (encryptbykey(key_guid('keycodeskey'), @key1), encryptbykey(key_guid('keycodeskey'), @key2), current_timestamp)", cx);         cx.open();         cmd.parameters.addwithvalue("@key1",key1.tostring());         cmd.parameters.addwithvalue("@key2", key2.tostring());         int success = cmd.executenonquery(); 

i not getting errors when @ unencrypted data, single digit number. if hard code parameters, not work either. works if actual numbers in sqlcommand.

any or advice appreciated!

this code ended using:

    sqlcommand cmd = new sqlcommand(@"open symmetric key keycodeskey decryption certificate keycodes;      insert keyfile(encrypted_key1, encrypted_key2, startingkeydate) values (encryptbykey(key_guid('keycodeskey'),"+key1.tostring()+@"), encryptbykey(key_guid('keycodeskey'), "+key2.tostring()+@"), current_timestamp)", cx);     cx.open();      int success = cmd.executenonquery();     cx.close() 

since windows forms application , there no possibility of injection issues, best solution come works.