基础知识

String

chop\chop!

会去掉字符串最后的一个字符。

chomp、chmop!

则从字符串中摘除行尾的分隔符。通常是换行符。

String.delete(",")删除某个字符

require 'rubygems'

require 'net/ping'

if Net::PingExternal.new('www.google.com').ping

   puts "Pong!"

else  puts "No Response"

end

 

ruby域名解析

requrie 'resolv'

puts Resolv.getaddress("www.mdoss.com")

--> 203.86.16.168

得到主机名关联的所有地址. each_address

require 'resolv'

Resolv.each_address("www.baidu.com") do |ip|

          puts ip

end

用getname方法把IP地址转换成主机名.

ip= "192.0.34.166"

begin

   puts Resolv.getname(ip)

rescue

   puts "No hostname associated with #{ip}"

end

**发送邮件

require "resolv"

require 'net/smtp'

to = '[e-mail]'

from = '[e-mail]'

message =<<MESSAGE_END

From:#{from}

To:#{to}

Subject:Your Sister

This is a test e-mail message.

MESSAGE_END

to_domain = to.match(/\@(.+)/)[1]

Resolv::DNS.open do |dns|

   mail_servers = dns.getresources(to_domain,Resolv::DNS::Resource::IN::MX)

   mail_server = mail_servers [rand(mail_servers.size)].exchange.to_s

   Net::SMTP.start(mail_server) do |smtp|

          smtp.send_message message,from,to

    end

end