Question

puts 'guess my favorite num'
x = gets.chomp
unless x.kind_of?(Fixnum)
  puts "it's not a Numeric symbol"
  if x=="2"
    puts "Well done!"
    if x!=2 || x.is_a?(Fixnum)
      puts "Try more, dude"
    end
  end
end

尝试学习ruby，但我的代码不起作用:-(需要3个不同条件的var。哪里有bug？

Answer 1

考虑一下：

#!/usr/bin/env ruby
puts "Guess my favorite num."
x = gets.chomp
begin
  if Integer(x) == 2
    puts "Well done!"
  else
    puts "Try more, dude."
  end
rescue ArgumentError
  puts "It's not an integer."
end

Answer 2

半人为的例子，但你可能正在寻找elsif：

puts 'enter a favorite num'
x = gets.chomp.to_i
if x == 2
  puts "you entered 2"
elsif x !=2
  puts "you did not enter 2"
end

另外 - 正如@Jan Dvorak指出的那样 - gets方法返回一个字符串，你想要转换它（在这种情况下为整数）。

另一个解决方案是使用case语句：

print 'enter a favorite num'
x = gets.chomp.to_i
case x
when 2
  puts "you entered 2"
else
  puts "you did not enter 2"
end

Answer 3

你可能意味着类似的东西：

loop do
  puts 'guess my favorite num'
  x = gets.chomp
  case x
  when /\D/
    puts "it's not a Numeric symbol"
  when "2"
    puts "Well done!"
    break
  else
    puts "Try more, dude"
  end
end

Ruby if语句3条件

3 个答案: