红宝石 |日期 downto()函数

Date#downto()是 Date 类方法，相当于 step(min, -1){|date| …} 并返回枚举数。

Syntax: Date.downto()

Parameter: Date values

Return: equivalent to step(min, -1){|date| …} and returns the enumerator.

示例 #1：

# Ruby code for Date.downto() method
  
# loading date
require 'date'
  
# declaring Date 
a = Date.new(2019, 1, 1)
  
# declaring Date
b = Date.jd(2452004)
  
# declaring Date
c = Date.ordinal(2019, 12)
  
# Date 
puts "Date a : #{a}\n\n"
puts "Date b : #{b}\n\n"
puts "Date c : #{c}\n\n\n\n"
  
  
# downto form 
puts "Date a downto form : #{a.downto(23)}\n\n"
puts "Date b downto form : #{b.downto(21)}\n\n"
puts "Date c downto form : #{c.downto(5)}\n\n"

输出 ：

Date a : 2019-01-01

Date b : 2001-04-04

Date c : 2019-01-12



Date a downto form : #

Date b downto form : #

Date c downto form : #

示例 #2：

# Ruby code for Date.downto() method
  
# loading date
require 'date'
  
# declaring Date 
a = Date.parse('2019-01-01')
  
# declaring Date
b = Date.strptime('03-12-2019', '%d-%m-%Y')
  
# declaring Date
c = Date.commercial(2019, 5, 6)
  
# Date 
puts "Date a : #{a}\n\n"
puts "Date b : #{b}\n\n"
puts "Date c : #{c}\n\n\n\n"
  
  
# downto form 
puts "Date a downto form : #{a.downto(23)}\n\n"
puts "Date b downto form : #{b.downto(21)}\n\n"
puts "Date c downto form : #{c.downto(5)}\n\n"

输出 ：

Date a : 2019-01-01

Date b : 2019-12-03

Date c : 2019-02-02



Date a downto form : #

Date b downto form : #

Date c downto form : #