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Ruby on rails 如何检查params中的参数是否存在?_Ruby On Rails_Ruby_Devise - Fatal编程技术网

Ruby on rails 如何检查params中的参数是否存在?

Ruby on rails 如何检查params中的参数是否存在?,ruby-on-rails,ruby,devise,Ruby On Rails,Ruby,Devise,如何检查参数是否为空 params.require(:user).permit(:email) 我试过了 if params.require(:recovery_password).permit(:email).blank? 但出现以下错误: param is missing or the value is empty: recovery_password 我想这对你会有用的 if params[:user][:email].blank? ..... end 保持编码和学习

如何检查参数是否为空

params.require(:user).permit(:email)
我试过了

if params.require(:recovery_password).permit(:email).blank?
但出现以下错误:

param is missing or the value is empty: recovery_password

我想这对你会有用的

if params[:user][:email].blank?
  .....
end
保持编码和学习