[HELP] Form submitted even when empty.

1. For form validation in front end you can use jquery validation library.
2. For user registering/login functions I suggest you to use Codeigniter Ion Auth Library. It has a lot of nice functionalities.
3. In CI backend form validation you should use CI form validation library. Ion Auth library uses it, you can extend your rules according to your needs

As for the 2nd suggestion for using the Ion Auth Library.
Since i'm kinda new in CI.. 
If i have a project which is online and has some users registered in it.. Is it possible to embed it later in the project? Without affecting the users experience and accounts?

I hope you understand what i mean.

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