Question

如何在If Else语句 check 中分配局部变量，然后在所说的If Else block 中使用该变量。这就是我的意思：

      def try_if_else(foo)
        if bar = other_method(foo) == true
          do_something_with_bar(bar)
        else
          do_something_else(foo)
        end
      end

这是我尝试使用的实际方法，但没有成功：

      def try_to_find_site(location)
        if (response = findplacefromtext_textquery(location)[:status]) == 'OK'
          convert_findplacefromtext_to_struct(response)
        elsif (response = findplacefromtext_phonenumber(location)[:status]) == 'OK'
          convert_findplacefromtext_to_struct(response)
        elsif (response = textsearch(location)[:status]) == 'OK'
          convert_textsearch_to_struct(response)
        else
          [LocationStruct.new('Sorry, your business was not found, try the manual method', '', '', '')]
        end
      end

这是我设法开始工作的方法，但并不理想，因为它两次调用了外部API来返回我要查找的结果：

      def try_to_find_site(location)
        if findplacefromtext_textquery(location)[:status] == 'OK'
          convert_findplacefromtext_to_struct(findplacefromtext_textquery(location))
        elsif findplacefromtext_phonenumber(location)[:status] == 'OK'
          convert_findplacefromtext_to_struct(findplacefromtext_phonenumber(location))
        elsif textsearch(location)[:status] == 'OK'
          convert_textsearch_to_struct(textsearch(location))
        else
          [LocationStruct.new('Sorry, your business was not found, try the manual method', '', '', '')]
        end
      end

如果需要查看我要做什么，这里是整个文件：

# Handles consuming the Google Api.
# require 'httparty'
module ApiHandlers
  module GoogleMaps
    class GoogleBusinessFinder
      include HTTParty
      debug_output $stdout
      base_uri 'https://maps.googleapis.com'
      default_params key: Rails.application.credentials.development[:google][:secret_key]
      def initialize(location)
        @location = location
      end

      def call
        try_to_find_site(location)
      end

      # THESE BE PRIVATE Matey! YARR!!

      private

      LocationStruct = Struct.new(:name, :formatted_address, :place_id, :rating)

      # Tries various the various (findplacefromtext_textquery, findplacefromtext_phonenumber, textsearch)
      #  methods of finding the business and returns an array of structs with findings.
      def try_to_find_site(location)
        if findplacefromtext_textquery(location)[:status] == 'OK'
          convert_findplacefromtext_to_struct(findplacefromtext_textquery(location))
        elsif findplacefromtext_phonenumber(location)[:status] == 'OK'
          convert_findplacefromtext_to_struct(findplacefromtext_phonenumber(location))
        elsif textsearch(location)[:status] == 'OK'
          convert_textsearch_to_struct(textsearch(location))
        else
          [LocationStruct.new('Sorry, your business was not found, try the manual method', '', '', '')]
        end
      end

      def convert_findplacefromtext_to_struct(response)
        response = response[:candidates][0]
        [LocationStruct.new(response[:name], response[:formatted_address], response[:place_id], response[:rating])]
      end

      def convert_textsearch_to_struct(response)
        response = response[:results]
        response.map { |response| LocationStruct.new(response[:name], response[:formatted_address], response[:place_id], response[:rating]) }
      end

      # Tries to find the business using the business name and address
      def findplacefromtext_textquery(location)
        @options = {
          query: { inputtype: 'textquery',
                   input: "#{location.location_name} #{readable_address(location)}",
                   fields: 'name,formatted_address,name,types,rating,place_id,id' }
        }
        self.class.get('/maps/api/place/findplacefromtext/json', @options).parsed_response.deep_symbolize_keys
      end

      # Tries to find the business using the business phone number
      def findplacefromtext_phonenumber(location)
        @options = {
          query: { inputtype: 'phonenumber',
                   input: "+1#{location.phone_number}",
                   fields: 'name,formatted_address,name,types,rating,place_id' }
        }
        self.class.get('/maps/api/place/findplacefromtext/json', @options).parsed_response.deep_symbolize_keys
      end

      # Finds an array of businesses that match the parameters. Last chance to find it.
      def textsearch(location)
        @options = {
          query: { query: "#{location.location_name} #{location.city} #{location.country}",
                   fields: 'name,formatted_address,name,types,rating,place_id,id' }
        }
        self.class.get('/maps/api/place/textsearch/json', @options).parsed_response.deep_symbolize_keys
      end

      def readable_address(location)
        "#{location.address_line_1} #{location.city} #{location.region} #{location.country} #{location.postal_code}"
      end
      attr_reader :location
      # is equal to:
      # def location
      #   @location
      # end
    end
  end
end

谢谢！

Answer 1

一种方法是分为两种方法：

def try_to_find_site(location)
  find_site(location) || [LocationStruct.new('Sorry, your business was not found, try the manual method', '', '', '')]
end

def find_site(location)

  text_query = findplacefromtext_textquery(location)
  return convert_findplacefromtext_to_struct(text_query) if text_query[:status] == 'OK'

  phone_number = findplacefromtext_phonenumber(location)
  return convert_findplacefromtext_to_struct(phone_number) if phone_number[:status] == 'OK'

  text_search = textsearch(location)
  return convert_textsearch_to_struct(text_search) if text_search[:status] == 'OK'

end

还要确保对方法名称遵循一些约定，因为这会使眼睛流血...

Answer 2

您在正确的轨道上，但是括号放在错误的位置，因此您将response设置为"OK"。相反，您想要：

  def try_to_find_site(location)
    if (response = findplacefromtext_textquery(location))[:status] == 'OK'
      convert_findplacefromtext_to_struct(response)
    elsif (response = findplacefromtext_phonenumber(location))[:status] == 'OK'
      convert_findplacefromtext_to_struct(response)
    elsif (response = textsearch(location))[:status] == 'OK'
      convert_textsearch_to_struct(response)
    else
      [LocationStruct.new('Sorry, your business was not found, try the manual method', '', '', '')]
    end
  end

Answer 3

我会这样实现：

FINDERS = {findplacefromtext_textquery: :convert_findplacefromtext_to_struct,
          findplacefromtext_phonenumber: :convert_findplacefromtext_to_struct,
          convert_textsearch_to_struct: :textsearch}

def try_to_find_site(location)
  response = FINDERS.detect do |finder,converter|
    r = send(finder,location)
    break send(converter,r) if r[:status] == 'OK'
  end 
  response || [LocationStruct.new('Sorry, your business was not found, try the manual method', '', '', '')]
end

在这里，我们只是循环遍历方法，返回的第一个方法也将转换并分配给响应。如果未找到任何内容，则返回默认值

如何在If else陈述检查中分配变量

3 个答案: