ruby 生成随机数 和 随机字符串

1,rand(999999) 生成 6 位随机数

irb(main):047:0> rand(111111..999999)
=> 259628
irb(main):048:0> rand(111111..999999)
=> 813383
irb(main):049:0> rand(111111..999999)
=> 816504
irb(main):050:0> rand(111111..999999)
=> 499279
irb(main):051:0> rand(111111..999999)
=> 793555


2,puts rand(0xffffff) # 十六进制的


3,puts rand 生成 0-1 之间的任意数


4,  def newpass( len )
chars = ("a".."z").to_a + ("A".."Z").to_a + ("0".."9").to_a
newpass = ""
1.upto(len) { |i| newpass << chars[rand(chars.size-1)] }
return newpass
end

rand(15..46)
生成15<=x<=46的整数

第二次编辑

puts   newpass(15)


ref:
http://snippets.dzone.com/posts/show/491
http://stackoverflow.com/questions/88311/how-best-to-generate-a-random-string-in-ruby