接受用户输入
first_name = gets.chomp
首字母大写
first_name.capitalize!
字母变大写
first_name.upcase!
字母变小写
first_name.downcase!
多行输出
print <<EOF # 多行输出 EOF
注释
# 我是注释
变量获取
#{first_name}
变量
- 全局变量 $
- 类变量 @@
- 方法变量 @
- 局部变量 小写字母或_
if/else
if a < b puts '1' elsif b < a puts '2' end
类
class Classname def functionname(params) puts params end end class1 = Classname.new class1.functionname('1') unless unless false print 'ok' else print 'no' end
是否包含字符
print 'puts' user_input = gets.chomp user_input.downcase! if user_input.include"s" print 'has s' end
替换字符
# s -> th user_input.gsub!(/s/,"th")
在字符串中输出变量值
puts 'okok #{user_input}'
while
counter = 1 while counter < 11 puts counter counter = counter + 1 end
Until
counter = 1 until counter > 10 print counter counter = counter + 1 end
+= 、 -= 、 *=、 /=
Some languages have the increment operators ++ and -- (which also add or subtract 1 from a value), but Ruby does not
for循环
# 如果 1...10 包含1-9,如果 1..10 包含1-10
for num in 1...10 puts num end
Loop Method
An iterator is just a Ruby method that repeatedly invokes a block of code.
i = 20 loop do i -= 1 print "#{ i }" break if i <= 0 end
Next
i = 20 loop do i -= 1 next if i%2 != 0 print "#{i}" break if i <= 0 end
数组
my_array = [1,2,3,4,5]
The .each Iterator迭代器
numbers = [1, 2, 3, 4, 5] # one way to loop numbers.each { |item| puts item } # another way to loop numbers.each do |item| puts item end
The .times Iterator 次数迭代器
10.times { print 'ok'})
Looping with 'While'
num = 1 while num <= 50 do print num num += 1 end
Looping with 'Until'
num = 1 until num > 50 do print num num += 1 end
Loop the Loop with Loop
num = 0 loop do num += 1 print "Ruby!" break if num == 30 end
The .split Method,
text.split(",") puts "Text to search through: " text = gets.chomp puts "Word to redact" redact = gets.chomp words = text.split(" ") words.each do |word| print word end