1.下载安装包地址:http://rubyforge.org/frs/?group_id=167
2.安装rails命令: gem install rails --include-dependencies
我装的时候报错说
The 'XXX' native gem requires installed build tools.

Please update your PATH to include build tools or download the DevKit
from 'http://rubyinstaller.org/downloads' and follow the instructions
at 'http://github.com/oneclick/rubyinstaller/wiki/Development-Kit'
解决方案:
下载dev kit – DevKit-tdm-32-4.5.1-20101214-1400-sfx.exe

在安装目录下运行ruby dk.rb,然后按照提示分别运行ruby dk.rb init 和 ruby dk.rb install

然后重新安装rails就好了