【Ruby】语法记录一

#

• 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    endendclass1 = Classname.newclass1.functionname('1')

• unless

unless false    print 'ok'else    print 'no'end        

• 是否包含字符

print 'puts'user_input = gets.chompuser_input.downcase!if user_input.include?"s"   print 'has s'end

• 替换字符

// s -> thuser_input.gsub!(/s/,"th")

• 在字符串中输出变量值

puts 'okok #{user_input}'

• while

counter = 1while counter < 11    puts counter    counter = counter + 1end

• Until

counter = 1until counter > 10    print counter    counter = counter + 1end    

• += 、 -= 、 *=、 /=

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1-10for num in 1...10    puts numend    

• Loop Method

An iterator is just a Ruby method that repeatedly invokes a block of code.

i = 20loop do    i -= 1    print "#{ i }"    break if i <= 0end    

• Next

i = 20loop do  i -= 1  next if i%2 != 0  print "#{i}"  break if i <= 0end

• 数组

my_array = [1,2,3,4,5]

• The .each Iterator迭代器

numbers = [1, 2, 3, 4, 5]# one way to loopnumbers.each { |item| puts item }# another way to loopnumbers.each do |item|  puts itemend

• The .times Iterator 次数迭代器

10.times { print 'ok'})

• Looping with ‘While’

num = 1while num <= 50 do    print num    num += 1end    

• Looping with ‘Until’

num = 1until num > 50 do    print num    num += 1end    

• Loop the Loop with Loop

num = 0loop do    num += 1    print "Ruby!"    break if num == 30end    

• The .split Method,

text.split(",")puts "Text to search through: "text = gets.chompputs "Word to redact"redact = gets.chompwords = text.split(" ")words.each do |word|    print wordend