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The whole code has more problems except the encoding.

3. To the concrete problem: You may encode the problematic strings using base64 before storing within the password field, on reading apply base64 decoding. This is not a solution, better try to refactor the whole password related code.

Thank's for your reply, I have another problems, I can't change all value in the password field with base64 because the field passowrd has using by another application. If i change the password it will make big effect to anoher application

Do you have any better idea ? What part of my code have to change to solved my problems ?