How can we specify rules for jquery validation plugin by class?

Question

The jQuery Validation plugin works great and is very easy to use:

$(\".selector\").validate({
})

Just by setting css classes like \"require

Answer 1

I've built upon Starx's answer to create a repeatable easy to use function that uses the default methods and creates new error messages for specific classes. considering the fact that your specific class will only be used to override the message once you shouldn't have any conflicts reusing this for many different class names using any existing methods.

var CreateValidation = function(className, customMessage, validationMethod){
  var objectString = '{"'+ className +'": true}',
  validator = $.validator;

  validator.addMethod(
    className,
    validator.methods[validationMethod],
    customMessage
  );
  validator.addClassRules(
    className,
    JSON.parse(objectString)
  );
};

Usage Example with validation class being "validation-class-firstname":

CreateValidation('validation-class-firstname', 'Please enter first name', 'required');