Question

我正在尝试写一个类来存储禁令。我想检查某个IP是否被禁止并返回@ip，@time，@reason等。

class BannedIP
  attr_reader :ip, :time, :reason
  def initialize(ip, time, reason)
    @ip = ip
    @time = time
    @reason = reason
  end
  def banned?(ip)
    # What do I use here?
  end
end

我需要# What do I use here?部分的帮助，以便我可以执行以下操作：

if b = BannedIP.banned? '10.10.10.10'

Answer 1

我不确定当你已经知道ip有意义时回归ip，但是任何......

您可以使用自定义哈希类：

class BannedHash < Hash

  def ban(ip, time, reason)
      self[ip] = {time: time, reason: reason}
  end

  def banned?(ip)
      if self.include?(ip)
        self[ip]
      else
       "ip: #{ip} not found."
    end
  end

end

用法：

def main
    b = BannedHash.new
    b.ban("10.10.10.10", Time.now, "Some reason")
    puts b.banned?("10.10.10.10")
    puts b.banned?("11.11.11.11")
end

输出：

{:time=>2015-04-27 21:18:39 +1200, :reason=>"Some reason"}
ip: 11.11.11.11 not found.

Answer 2

安装mysql2和活动记录宝石

gem install mysql2
gem install active_record

然后执行以下代码快照

require 'active_record'
require 'mysql2'

SOURCE_CREDNTIALS =  {
    :adapter  => "mysql2",
    :host     => "localhost",
    :username => "root",
    :password => "password",
    :database => "banned_db"
}

class Banned < ActiveRecord::Base
  ActiveRecord::Base.establish_connection(SOURCE_CREDNTIALS)

  #attr_accessor :id, :ip, :banned_at, :reason

  def self.banned?(ip)
    where(ip: ip).count > 0
  end

end

现在你可以使用这个简单的类作为

user_foo = Banned.create(ip: '10.10.10.10', banned_at: Time.now, reason: 'violated terms and conditions')
Banned.banned?('10.10.10.10')

BannedIP.banned？方法将返回true或false，具体取决于是否禁止特定ip。

Answer 3

除非你打算在其中加入更多的东西，否则有一点浪费就可以获得完整的课程。如果只是这样，那么用数组跟踪它会更容易，并且花费更少的内存。

TextBox1.TextChanged

我该如何编写这个ruby类？

3 个答案: