undefined method `for' for #<' Devise::ParameterSanitizer:0x00007f0e320f79d0 '>

 NoMethodError in Devise::RegistrationsController#edit

用Devise套件作為系統的帳號管理功能，結果在這個檔案出現錯誤．

app/controller/application_controller.rb

class ApplicationController < ActionController::Base
  # Prevent CSRF attacks by raising an exception.
  # For APIs, you may want to use :null_session instead.
  protect_from_forgery with: :exception
  before_action :configure_permitted_parameters, if: :devise_controller?

  protected
  def configure_permitted_parameters
    devise_parameter_sanitizer.for(:sign_up) { |u| u.permit(:username, :email, :password, :password_confirmation, :remember_me, :avatar, :avatar_cache) }
    devise_parameter_sanitizer.for(:account_update) { |u| u.permit(:username, :password, :password_confirmation, :current_password, :avatar) }
  end
end 

只要將for修正成permit，就可以了．

def configure_permitted_parameters
  devise_parameter_sanitizer.permit(:sign_up) {...}
  devise_parameter_sanitizer.permit(:account_update) {...}
end