最简单的方法肯定是在终端输入以下命令:

sudo gem update --system

如果不想下载文档，可以添加标记——no-document。下面是运行命令后的输出示例:

sudo gem update --system
Password:
Updating rubygems-update
Fetching: rubygems-update-2.6.8.gem (100%)
Successfully installed rubygems-update-2.6.8
Parsing documentation for rubygems-update-2.6.8
Installing ri documentation for rubygems-update-2.6.8
Installing darkfish documentation for rubygems-update-2.6.8
Installing RubyGems 2.6.8
RubyGems 2.6.8 installed
Parsing documentation for rubygems-2.6.8
Installing ri documentation for rubygems-2.6.8

------------------------------------------------------------------------------

RubyGems installed the following executables:
    /System/Library/Frameworks/Ruby.framework/Versions/2.0/usr/bin/gem

Ruby Interactive (ri) documentation was installed. ri is kind of like man
pages for ruby libraries. You may access it like this:
  ri Classname
  ri Classname.class_method
  ri Classname#instance_method

如果出现“需求安装失败，状态:1”的错误。，下面是该怎么做:

使用以下命令安装Homebrew(由于某些原因，它可能不会自动工作):

ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"

然后继续安装rvm

curl -sSL https://get.rvm.io | bash -s stable --ruby

退出，重新打开终端，然后:

rvm install 2.2
rvm use 2.2 --default

打开终端并运行

curl -sSL https://raw.githubusercontent.com/rvm/rvm/master/binscripts/rvm-installer | bash -s stable

完成后，您需要重新启动您的终端，以便rvm命令能够工作。

现在，运行rvm list known

这显示了Ruby解释器的版本列表。

现在，运行rvm install ruby@latest来获取最新的Ruby版本。

如果在终端中输入ruby -v，则应显示ruby x.x.x.x

如果它仍然显示ruby 2.0。，执行rvm use ruby-X.X命令。X——违约。

Windows 10操作系统的前提条件:

C编译器。你可以使用http://www.mingw.org/ 使命令可用，否则它将抱怨“bash: Make: command not found”。可以通过mingw-get install msys-make命令进行安装 在path环境变量中添加“C:\MinGW\msys\1.0\bin”和“C:\MinGW\bin”

我推荐rbenv* https://github.com/rbenv/rbenv

*如果这符合你的标准:https://github.com/rbenv/rbenv/wiki/Why-rbenv?:

rbenv does… Provide support for specifying application-specific Ruby versions. Let you change the global Ruby version on a per-user basis. Allow you to override the Ruby version with an environment variable. In contrast with RVM, rbenv does not… Need to be loaded into your shell. Instead, rbenv's shim approach works by adding a directory to your $PATH. Override shell commands like cd or require prompt hacks. That's dangerous and error-prone. Have a configuration file. There's nothing to configure except which version of Ruby you want to use. Install Ruby. You can build and install Ruby yourself, or use ruby-build to automate the process. Manage gemsets. Bundler is a better way to manage application dependencies. If you have projects that are not yet using Bundler you can install the rbenv-gemset plugin. Require changes to Ruby libraries for compatibility. The simplicity of rbenv means as long as it's in your $PATH, nothing else needs to know about it.

安装

安装Homebrew http://brew.sh

然后:

$ brew update
$ brew install rbenv ruby-build

# Add rbenv to bash so that it loads every time you open a terminal
echo 'if which rbenv > /dev/null; then eval "$(rbenv init -)"; fi' >> ~/.bash_profile
source ~/.bash_profile

$ rbenv install --list
Available versions:
 1.8.5-p113
 1.8.5-p114
 […]
 2.3.1
 2.4.0-dev
 jruby-1.5.6
 […]
$ rbenv install 2.3.1
[…]

设置全局版本:

$ rbenv global 2.3.1
$ ruby -v
ruby 2.3.1p112 (2016-04-26 revision 54768) [x86_64-darwin15]

如果您没有显示更新的版本，那么

$ rbenv rehash

通过在存储库根目录中添加.ruby-version来设置存储库的本地版本:

$ cd ~/whatevs/projects/new_repo
$ echo "2.3.1" > .ruby-version

对于OS X，请访问此链接。

酿造专用溶液

更好的解决方案

从评论(马克西姆·卢齐克的功劳)来看，我还没有测试过，但似乎是一个更优雅的解决方案:

通过brew安装Ruby后，运行以下命令将链接更新到最新的Ruby安装

一个解决方案

使用brew就足够了。没有必要安装rvm，对我来说，它只是复杂的事情。

通过brew install ruby，您实际上是在安装最新的ruby(目前是v2.4.0)。但是，您的路径首先找到2.0.0。要避免这种情况，只需更改优先级(源)。我通过改变~/来做到这一点。配置及设置:

导出路径= / usr /地方/ bin:美元的道路

在此之后，我发现捆绑器gem仍然使用2.0.0版本。只需重新安装:gem install bundler

sudo gem update --system

然后重启电脑