def validates_formatting_of(attribute, options = {})
      validation = Method.find(attribute, options)
      options.reverse_merge!(:with => validation.regex, :message => validation.message)
      self.validates_format_of(attribute, options)
    end
def validates_formatting_of(attribute, options = {})
      validation = Method.find(attribute, options)
      options.reverse_merge!(:with => validation.regex, :message => validation.message)
      self.validates_format_of(attribute, options)
    end
Using validates_formatting_of is as simple as using Rails' built-in
 validation methods in models.

 class User < ActiveRecord::Base
   validates_formatting_of :email, :using => :email
 end

 If your column name is idencital to any of the built-in methods, you
 may leave off the `:using` option and validates_formatting_of will
 automatically use the validation with the matching name.

 class User < ActiveRecord::Base
   validates_formatting_of :email
 end

 You can also pass conditions and options for Rails to use
 * :if
 * :unless
 * :allow_nil
 * :allow_blank
 * :on