有机会再试一试Rails了，只是原来接触的是2，现在已然变成了4，似乎现在的安装比原来会快些。。

Rails 4 安装

针对于安装了RVM
复制代码 代码如下:gem install rails
没有的话应该这样：
复制代码 代码如下:sudo gem install rails
安装RVM可以用句
复制代码 代码如下:curl -L https://get.rvm.io | bash -s stable

查看rails版本

复制代码 代码如下:rails -v
Rails 4.0.3
似乎这就是当前的最新版本

Ruby版本

复制代码 代码如下:We recommend Ruby 2.1.0 for use with Rails. We stopped supporting Ruby 1.8.x after Rails 3.2. Ruby 1.9.2+ will be supported until Rails 5.

官方推荐用2.1.0. 也就是最新版本

安装SQLite

似乎这就是诸如Django、Rails这类对于轻量级网站的数据库要求。

如果是mac os

复制代码 代码如下:brew install sqlite3
其他可以看情况安装，如openSUSE
复制代码 代码如下:sudo zypper install sqlite3


Rails 4 Hello,World

可以直接用rails生成
复制代码 代码如下:$rails new hello
于是就有了
复制代码 代码如下:
create
create README.rdoc
create Rakefile
create config.ru
create .gitignore
create Gemfile
create app
create app/assets/javascripts/application.js
create app/assets/stylesheets/application.css
create app/controllers/application_controller.rb
create app/helpers/application_helper.rb
create app/views/layouts/application.html.erb
create app/assets/images/.keep
create app/mailers/.keep
create app/models/.keep
create app/controllers/concerns/.keep
create app/models/concerns/.keep
create bin
create bin/bundle
create bin/rails
create bin/rake
create config
create config/routes.rb
create config/application.rb
create config/environment.rb
create config/environments
create config/environments/development.rb
create config/environments/production.rb
create config/environments/test.rb
create config/initializers
create config/initializers/backtrace_silencers.rb
create config/initializers/filter_parameter_logging.rb
create config/initializers/inflections.rb
create config/initializers/mime_types.rb
create config/initializers/secret_token.rb
create config/initializers/session_store.rb
create config/initializers/wrap_parameters.rb
create config/locales
create config/locales/en.yml
create config/boot.rb
create config/database.yml
create db
create db/seeds.rb
create lib
create lib/tasks
create lib/tasks/.keep
create lib/assets
create lib/assets/.keep
create log
create log/.keep
create public
create public/404.html
create public/422.html
create public/500.html
create public/favicon.ico
create public/robots.txt
create test/fixtures
create test/fixtures/.keep
create test/controllers
create test/controllers/.keep
create test/mailers
create test/mailers/.keep
create test/models
create test/models/.keep
create test/helpers
create test/helpers/.keep
create test/integration
create test/integration/.keep
create test/test_helper.rb
create tmp/cache
create tmp/cache/assets
create vendor/assets/javascripts
create vendor/assets/javascripts/.keep
create vendor/assets/stylesheets
create vendor/assets/stylesheets/.keep
run bundle install
接着会安装包依赖
复制代码 代码如下:
Fetching gem metadata from https://rubygems.org/..........
Fetching additional metadata from https://rubygems.org/..
Resolving dependencies...
Using rake (10.3.1)
Using i18n (0.6.9)
Using minitest (4.7.5)
Using multi_json (1.9.2)
Using thread_safe (0.3.3)
Using tzinfo (0.3.39)
Using activesupport (4.0.3)
Using builder (3.1.4)
Using erubis (2.7.0)
Using rack (1.5.2)
Using rack-test (0.6.2)
Using actionpack (4.0.3)
Using mime-types (1.25.1)
Using polyglot (0.3.4)
Using treetop (1.4.15)
Using mail (2.5.4)
Using actionmailer (4.0.3)
Using activemodel (4.0.3)
Using activerecord-deprecated_finders (1.0.3)
Using arel (4.0.2)
Using activerecord (4.0.3)
Using bundler (1.5.3)
Using coffee-script-source (1.7.0)
Using execjs (2.0.2)
Using coffee-script (2.2.0)
Using thor (0.19.1)
Using railties (4.0.3)
Using coffee-rails (4.0.1)
Using hike (1.2.3)
Using jbuilder (1.5.3)
Using jquery-rails (3.1.0)
Using json (1.8.1)
Using tilt (1.4.1)
Using sprockets (2.11.0)
Using sprockets-rails (2.0.1)
Using rails (4.0.3)
Using rdoc (4.1.1)
Using sass (3.2.19)
Using sass-rails (4.0.3)
Using sdoc (0.4.0)
Using sqlite3 (1.3.9)
Using turbolinks (2.2.2)
Using uglifier (2.5.0)
Your bundle is complete!
Use `bundle show [gemname]` to see where a bundled gem is installed.

运行Rails

复制代码 代码如下: $rails server
这样的话打开 http://localhost:3000 就可以看到,Rails的欢迎界面Welcome aboard，有点类似于Django-CMS的小马哥~~

创建controller

如官方指南所说http://guides.rubyonrails.org/getting_started.html

执行命令：
复制代码 代码如下:$rails generate controller welcome index
就会创建下面这些文件：
复制代码 代码如下:
create app/controllers/welcome_controller.rb
route get "welcome/index"
invoke erb
create app/views/welcome
create app/views/welcome/index.html.erb
invoke test_unit
create test/controllers/welcome_controller_test.rb
invoke helper
create app/helpers/welcome_helper.rb
invoke test_unit
create test/helpers/welcome_helper_test.rb
invoke assets
invoke coffee
create app/assets/javascripts/welcome.js.coffee
invoke scss
create app/assets/stylesheets/welcome.css.scss

在config/routes.rb添加默认页面
复制代码 代码如下:root 'welcome#index'
再运行
复制代码 代码如下:rails server
就会出现

复制代码 代码如下:Welcome#index

Find me in app/views/welcome/index.html.erb

一切来得很快，很突然。