Parsley's default DOM API is Parsley adds many classes and elements in the DOM when it validates.You are strongly encouraged to customize them in your own stylesheets, but here is the "standard" Parsley css file that is used here on the documentation and examples, if you want to use it to bootstrap your projects with Parsley.Second, it requires that the back-end code be customized to meet the needs of each form.
This can make filling out the form tedious, and people might stop in the middle.
Once the code has been loaded, invoking the validation plugin is simple: The ID (myform) tells the plugin where to find your form.
The validation plugin code then hooks itself into the form, observing the fields and blocking the submit action until validation passes.
Usually, any information submitted is reviewed by an administrator in any case, and what's most important is that the user have a good experience. Java Script observers are placed on each form field, and when the user enters information, the Java Script code validates its format and, if necessary, displays an error message and blocks the form from being submitted.
In practice, form validation is a complex technical and user experience challenge, and it requires a substantial amount of Java Script programming.
Parsley comes with various error messages for its built-in validators.