ruby控制语句和循环语句

6.ruby控制语句

def sounds(str)

if str == "mimi"

puts "It is a cat."

elsif str == "wowo"

puts "It is a dog."

elsif str == "gaga"

puts "It is a duck."

else

puts "unknown."

end

end

7.循环

(1)while ，用于自由指定条件

i=0

sum=0

while i<=100

sum += i

i += 1

end

i

=>101

sum

=>5050

(2)until语句 （当条件不成立的时候执行）

i = 5

until i<5

puts "haha"

i -= 1

end

(3)for 用于

i=0

sum=0

for i in 0 .. 100

sum += i

end

sum

=>5050

(4)times方法,用于指定循环次数

5.times{

print("Ruby!\n')

}

5.times do

puts "aa"

end

do end <==> {}

(5)each .用于从对象中逐个取元素

i=0

a = %w{Perl Python Ruby Scheme}

a.each{|lang|

i +=1

if i ==3

break

end

puts "#{i},#{lang}"

}

break 跳出循环

next 跳到下一次循环，有点像continue

redo 以相同的条件进行此次循环

(6)LOOP

loop{

break/next/redo

}

参考链接：http://blog.sina.com.cn/s/blog_5d2dc2e50100ha6s.html