10.times do 
  alphabet = ('a'..'z').to_a
  string += alpha[rand(alpha.length)]
end

以下内容对我很有用

def generate_random_password(min_length, max_length)
    length = SecureRandom.random_number(max_length - min_length) + min_length
    character_sets = [ 
      ('a'..'z').to_a,
      ('A'..'Z').to_a,
      ('0'..'9').to_a,
      "~!@^&*()_-+=[]|:;<,>.?".split('')
    ]   
    retval = []
    #   
    # Add one character from each set
    #   
    character_sets.each do |character_set|
      character = character_set[SecureRandom.random_number(character_set.count)]
      retval.push character
    end 
    #   
    # Fill the rest of the password with a random character from a random set
    #   
    i = character_sets.count - 1 
    while i < length
      character_set = character_sets[SecureRandom.random_number(character_sets.count)]
      character = character_set[SecureRandom.random_number(character_set.count)]
      retval.push character
      i += 1
    end
    retval.shuffle.join
  end

我不记得我在哪里找到了这个，但对我来说，它似乎是最好的，也是最不需要的过程：

def random_string(length=10)
  chars = 'abcdefghjkmnpqrstuvwxyzABCDEFGHJKLMNPQRSTUVWXYZ0123456789'
  password = ''
  length.times { password << chars[rand(chars.size)] }
  password
end

使用此方法，您可以传入一个很短的长度。默认设置为6。

def generate_random_string(length=6)
  string = ""
  chars = ("A".."Z").to_a
  length.times do
    string << chars[rand(chars.length-1)]
  end
  string
end

这个解决方案需要外部依赖性，但看起来比另一个更漂亮。

安装gem fakerFaker:：Lorem.characters（10）#=>“ang9cbhoa8”

SecureRandom.base64(15).tr('+/=lIO0', 'pqrsxyz')

来自Devise的东西