Question

我有一个方法，试图搜索定位与指定键和值匹配的每个记录的数组。

def search(key, query)
     some_stuff = [{"title"=>"Awesome Book", "author"=>"John Doe", "qty"=>"5"}, {"title"=>"Another Book", "author"=>"Jane Doe", "qty"=>"2"}, {"title"=>"Ruby Book", "author"=>"John Hancock", "qty"=>"4"}]
    # If I put the following in the block it will return has records 
    #however how do I substitute with key and query?
    some_stuff.select {|b| b[].include? "jo" }
    if matches.any?
       # has records
    else
       # has no records
    end
end

# If i call object.search(author, jo)
# I want to return the two records containing authors names with "jo" in them

# Similarly if I call object.search(title, rub)
# I want the query to return 1 record

另外，您将如何按指定字段对其进行排序

目前我正在考虑使用开关，但我几乎可以肯定有更简单的方法

Answer 1

require 'pp'

SOME_STUFF = [
  {"title"=>"Another Book", "author"=>"Jane Doe", "qty"=>"2"}, 
  {"title"=>"Ruby Book", "author"=>"John Hancock", "qty"=>"4"},
  {"title"=>"Awesome Book", "author"=>"John Doe", "qty"=>"5"},
]

def search(key, query)
  SOME_STUFF.select {|record| record[key].downcase.include? query }
end


pp search('author', 'jo')
pp search('title', 'ru')

 --output:--
[{"title"=>"Ruby Book", "author"=>"John Hancock", "qty"=>"4"},
 {"title"=>"Awesome Book", "author"=>"John Doe", "qty"=>"5"}]
[{"title"=>"Ruby Book", "author"=>"John Hancock", "qty"=>"4"}]

另外，您将如何按指定字段对其进行排序

require 'pp'

SOME_STUFF = [
  {"title"=>"Another Book", "author"=>"Jane Doe", "qty"=>"2"}, 
  {"title"=>"Ruby Book", "author"=>"John Hancock", "qty"=>"4"},
  {"title"=>"Awesome Book", "author"=>"John Doe", "qty"=>"5"},
]

def search(key, query)
  SOME_STUFF.select do |record| 
    record[key].downcase.include? query 
  end.sort_by {|hash| hash[key]}
end


pp search('author', 'jo')
pp search('title', 'ru')

--output:--
[{"title"=>"Awesome Book", "author"=>"John Doe", "qty"=>"5"},
 {"title"=>"Ruby Book", "author"=>"John Hancock", "qty"=>"4"}]
[{"title"=>"Ruby Book", "author"=>"John Hancock", "qty"=>"4"}]

编辑：

require 'pp'

class Book

  def title
    @title
  end

  def title=(val)
    @title = val
  end

  attr_accessor :author, :qty  #Same as above for author, qty


SOME_STUFF = [
  Book.new("Ruby Book", "John Hancock", 4),
  Book.new("Another Book", "Jane Doe", 2),
  Book.new("Awesome Book", "John Doe", 5),
]

def search(key, query)
  SOME_STUFF.select do |book| 
    book.send(key).downcase.include? query 
  end.sort_by {|book| book.send(key)}
end


pp search('author', 'jo')
pp search('title', 'ru')


--output:--

[#<Book:0x00000100929590 @author="John Doe", @qty=5, @title="Awesome Book">,
 #<Book:0x00000100933270 @author="John Hancock", @qty=4, @title="Ruby Book">]
[#<Book:0x00000100933270 @author="John Hancock", @qty=4, @title="Ruby Book">]

send（）方法接受一个字符串/符号（或包含字符串/符号的变量）作为参数，然后send（）基本上说，“嘿ruby，调用我在左边的对象上指定的方法。 “当你拥有所有方法时，需要在对象上调用方法名称作为字符串在许多编程语言中很常见。 ruby为我们发送了send（）。

如何在ruby中返回数组中特定哈希键的值？

1 个答案: