Question

我将此作为我的代码：

def index
  @monkeys = Monkey.where(owner: current_user)
end

def new
  @monkey = Monkey.new name: 'Monkey 1', alive: true, owner: current_user
end

def create
  @monkey = Monkey.create monkey_params
  # Other fields and save here
end

def edit
  @monkey = Monkey.find_by(id: params[:id], owner: current_user)
  check_on_monkey_first(@monkey)
end

def update
  @monkey = Monkey.find_by(id: params[:id], owner: current_user)
  check_on_monkey_first(@monkey)

  if @monkey.update(monkey_params)
    redirect_to monkeys_path, success: 'Monkey saved'
  end
end

private
def check_on_monkey_first(monkey)
  redirect_to monkeys_path, flash: {info: "Monkey doesn't exist"} and return unless monkey
  redirect_to monkeys_path, flash: {info: "Monkey no longer exist"} and return if !monkey.alive?
end

def monkey_params
  # some_fields_here
end

我认为＆＃34; ...并返回＆＃34;只提前退出check_on_monkey_first，然后继续update。

如果我不是Monkey的所有者，find_by将无法获得记录，并且应该执行redirect_to，因为Monkey将不存在。但它仍然会继续并在if @monkey.update(monkey_params)处中断代码，因为@monkey为零。

我如何做一个＆＃34; redirect_to some_path并返回＆＃34;在Ruby或Rails？如何立即停止并执行redirect_to？

Answer 1

可能有几种解决方案，但可能会返回一个布尔值，表明您正在触发重定向。例如：

def update
  @monkey = Monkey.find_by(id: params[:id], owner: current_user)

  if check_on_monkey_first(@monkey) and @monkey.update(monkey_params)
    redirect_to monkeys_path, success: 'Monkey saved'
  end
end

private
def check_on_monkey_first(monkey)
  redirect_to monkeys_path, flash: {info: "Monkey doesn't exist"} and return false unless monkey
  redirect_to monkeys_path, flash: {info: "Monkey no longer exist"} and return false if !monkey.alive?
  return true
end

更清晰的解决方案可能是对某些操作使用before_action（或before_filter用于Rails＆lt; v4）。但是，对于您要执行check_on_monkey_first检查的位置，它可能会降低灵活性。对于您的特定用例，您可以尝试：

before_action :check_on_monkey_first, only: [:edit, :update]

然后将check_on_monkey_first修改为：

def check_on_monkey_first
  @monkey = Monkey.find_by(id: params[:id], owner: current_user)
  redirect_to monkeys_path, flash: {info: "Monkey doesn't exist"} and return unless @monkey
  redirect_to monkeys_path, flash: {info: "Monkey no longer exist"} and return if !@monkey.alive?
end

您的update行动将成为：

def update
  if @monkey.update(monkey_params)
    redirect_to monkeys_path, success: 'Monkey saved'
  end
end

这可以让您删除需要它的操作中的检查（编辑和更新），您不必处理双重重定向，它应该自动为您设置这些操作的变量。

Answer 2

您可以使用仅适用于edit和update的{{3}}。

class YourController < ApplicationController
  before_action :check_on_monkey_first, :only => [:edit, :update]

  # other actions ...

  def edit
  end

  def update
    if @monkey.update(monkey_params)
      redirect_to monkeys_path, success: 'Monkey saved'
    end
  end

  private
  def check_on_monkey_first
    @monkey = Monkey.find_by(id: params[:id], owner: current_user)
    if @monkey.nil?
      redirect_to monkeys_path, flash: {info: "Monkey doesn't exist"}
    elsif not @monkey.alive?
      redirect_to monkeys_path, flash: {info: "Monkey no longer exist"}
    end
  end
end

Answer 3

请尝试：

private
def check_on_monkey_first(monkey)
  unless monkey
    redirect_to monkeys_path, flash: {info: "Monkey doesn't exist"}
    return 
  else
    unless monkey.alive?
      redirect_to monkeys_path, flash: {info: "Monkey no longer exist"}
      return
    end
  end
end

怎么办“redirect_to并返回”完全退出或立即redirect_to？

3 个答案: