You are welcome to join one of our open mapping projects over on the issue queue and use these best practice mapping guides.These guides are licensed under Public Domain (CC0), if you would like to contribute or have an feedback on these, please feel free to raise an issue in this repository.Defining validation rules makes form handling much, much easier.
You can find detailed instructions on how to do this in the Custom validators can also be asynchronous.
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Data validation is an important part of any application, as it helps to make sure that the data in a Model conforms to the business rules of the application.
For example, you might want to make sure that passwords are at least eight characters long, or ensure that usernames are unique.