您可以在控制台中使用ANSI转义序列来完成此操作。我知道这适用于Linux和Mac OS X，但我不确定Windows控制台(cmd)是否支持ANSI。

我是用Java写的，但思想是一样的。

// Foreground color
public static final String BLACK_TEXT()   { return "\033[30m";}
public static final String RED_TEXT()     { return "\033[31m";}
public static final String GREEN_TEXT()   { return "\033[32m";}
public static final String BROWN_TEXT()   { return "\033[33m";}
public static final String BLUE_TEXT()    { return "\033[34m";}
public static final String MAGENTA_TEXT() { return "\033[35m";}
public static final String CYAN_TEXT()    { return "\033[36m";}
public static final String GRAY_TEXT()    { return "\033[37m";}

// Background color
public static final String BLACK_BACK()   { return "\033[40m";}
public static final String RED_BACK()     { return "\033[41m";}
public static final String GREEN_BACK()   { return "\033[42m";}
public static final String BROWN_BACK()   { return "\033[43m";}
public static final String BLUE_BACK()    { return "\033[44m";}
public static final String MAGENTA_BACK() { return "\033[45m";}
public static final String CYAN_BACK()    { return "\033[46m";}
public static final String WHITE_BACK()   { return "\033[47m";}

// ANSI control characters
public static final String RESET_COLORS() { return "\033[0m";}
public static final String BOLD_ON()      { return "\033[1m";}
public static final String BLINK_ON()     { return "\033[5m";}
public static final String REVERSE_ON()   { return "\033[7m";}
public static final String BOLD_OFF()     { return "\033[22m";}
public static final String BLINK_OFF()    { return "\033[25m";}
public static final String REVERSE_OFF()  { return "\033[27m";}

结合上面的答案，您可以实现一些类似于gem colorize的东西，而不需要另一个依赖项。

class String
  # colorization
  def colorize(color_code)
    "\e[#{color_code}m#{self}\e[0m"
  end

  def red
    colorize(31)
  end

  def green
    colorize(32)
  end

  def yellow
    colorize(33)
  end

  def blue
    colorize(34)
  end

  def pink
    colorize(35)
  end

  def light_blue
    colorize(36)
  end
end

我发明了这个方法。这不是什么大事，但很有效:

def colorize(text, color = "default", bgColor = "default")
    colors = {"default" => "38","black" => "30","red" => "31","green" => "32","brown" => "33", "blue" => "34", "purple" => "35",
     "cyan" => "36", "gray" => "37", "dark gray" => "1;30", "light red" => "1;31", "light green" => "1;32", "yellow" => "1;33",
      "light blue" => "1;34", "light purple" => "1;35", "light cyan" => "1;36", "white" => "1;37"}
    bgColors = {"default" => "0", "black" => "40", "red" => "41", "green" => "42", "brown" => "43", "blue" => "44",
     "purple" => "45", "cyan" => "46", "gray" => "47", "dark gray" => "100", "light red" => "101", "light green" => "102",
     "yellow" => "103", "light blue" => "104", "light purple" => "105", "light cyan" => "106", "white" => "107"}
    color_code = colors[color]
    bgColor_code = bgColors[bgColor]
    return "\033[#{bgColor_code};#{color_code}m#{text}\033[0m"
end

下面是如何使用它:

puts "#{colorize("Hello World")}"
puts "#{colorize("Hello World", "yellow")}"
puts "#{colorize("Hello World", "white","light red")}"

可能的改进包括:

colors和bgColors在每次调用该方法时都被定义，并且它们不会改变。 添加其他选项，如粗体，下划线，暗等。

这个方法对p无效，因为p会检查它的参数。例如:

p "#{colorize("Hello World")}"

将显示“\e[0;38mHello World\e[0m”

我用看跌、打印和Logger gem对它进行了测试，它工作得很好。

我对此进行了改进，并创建了一个类，因此colors和bgColors是类常量，colorize是类方法:

编辑:更好的代码风格，定义常量而不是类变量，使用符号而不是字符串，增加了更多的选项，如粗体，斜体等。

class Colorizator
    COLOURS = { default: '38', black: '30', red: '31', green: '32', brown: '33', blue: '34', purple: '35',
                cyan: '36', gray: '37', dark_gray: '1;30', light_red: '1;31', light_green: '1;32', yellow: '1;33',
                light_blue: '1;34', light_purple: '1;35', light_cyan: '1;36', white: '1;37' }.freeze
    BG_COLOURS = { default: '0', black: '40', red: '41', green: '42', brown: '43', blue: '44',
                   purple: '45', cyan: '46', gray: '47', dark_gray: '100', light_red: '101', light_green: '102',
                   yellow: '103', light_blue: '104', light_purple: '105', light_cyan: '106', white: '107' }.freeze

    FONT_OPTIONS = { bold: '1', dim: '2', italic: '3', underline: '4', reverse: '7', hidden: '8' }.freeze

    def self.colorize(text, colour = :default, bg_colour = :default, **options)
        colour_code = COLOURS[colour]
        bg_colour_code = BG_COLOURS[bg_colour]
        font_options = options.select { |k, v| v && FONT_OPTIONS.key?(k) }.keys
        font_options = font_options.map { |e| FONT_OPTIONS[e] }.join(';').squeeze
        return "\e[#{bg_colour_code};#{font_options};#{colour_code}m#{text}\e[0m".squeeze(';')
    end
end

你可以这样使用它:

Colorizator.colorize "Hello World", :gray, :white
Colorizator.colorize "Hello World", :light_blue, bold: true
Colorizator.colorize "Hello World", :light_blue, :white, bold: true, underline: true

While the other answers will do the job fine for most people, the "correct" Unix way of doing this should be mentioned. Since all types of text terminals do not support these sequences, you can query the terminfo database, an abstraction over the capabilites of various text terminals. This might seem mostly of historical interest – software terminals in use today generally support the ANSI sequences – but it does have (at least) one practical effect: it is sometimes useful to be able to set the environment variable TERM to dumb to avoid all such styling, for example when saving the output to a text file. Also, it feels good to do things right. :-)

你可以使用红宝石终端宝石。它需要一些C编译来安装;我可以在我的Ubuntu 14.10系统下安装它:

$ sudo apt-get install libncurses5-dev
$ gem install ruby-terminfo --user-install

然后，您可以像这样查询数据库(参见terminfo手册页的可用代码列表):

require 'terminfo' 
TermInfo.control("bold")
puts "Bold text"
TermInfo.control("sgr0")
puts "Back to normal."
puts "And now some " + TermInfo.control_string("setaf", 1) + 
     "red" + TermInfo.control_string("sgr0") + " text."

这里有一个小的包装器类，我把它放在一起使事情更容易使用。

require 'terminfo'

class Style
  def self.style() 
    @@singleton ||= Style.new
  end

  colors = %w{black red green yellow blue magenta cyan white}
  colors.each_with_index do |color, index|
    define_method(color) { get("setaf", index) }
    define_method("bg_" + color) { get("setab", index) }
  end

  def bold()  get("bold")  end
  def under() get("smul")  end
  def dim()   get("dim")   end
  def clear() get("sgr0")  end

  def get(*args)
    begin
      TermInfo.control_string(*args)
    rescue TermInfo::TermInfoError
      ""
    end
  end
end

用法:

c = Style.style
C = c.clear
puts "#{c.red}Warning:#{C} this is #{c.bold}way#{C} #{c.bg_red}too much #{c.cyan + c.under}styling#{C}!"
puts "#{c.dim}(Don't you think?)#{C}"

(编辑)最后，如果你不想要一个gem，你可以依赖tput程序，如下所述- Ruby示例:

puts "Hi! " + `tput setaf 1` + "This is red!" + `tput sgr0`

我发现了一些:

http://github.com/ssoroka/ansi/tree/master

例子:

puts ANSI.color(:red) { "hello there" }
puts ANSI.color(:green) + "Everything is green now" + ANSI.no_color

http://flori.github.com/term-ansicolor/

例子:

print red, bold, "red bold", reset, "\n"
print red(bold("red bold")), "\n"
print red { bold { "red bold" } }, "\n"

http://github.com/sickill/rainbow

例子:

puts "this is red".foreground(:red) + " and " + "this on yellow bg".background(:yellow) + " and " + "even bright underlined!".underline.bright

如果你在Windows上，你可能需要做一个“gem install win32console”来启用对颜色的支持。

另外，如果您需要创建自己的gem，为控制台Ruby-script输出着色这篇文章也很有用。它解释了如何向字符串添加ANSI着色。你可以用这个知识把它包装在一些类中，这些类扩展了字符串或其他东西。

以下是我不需要任何宝石就能让它工作的方法:

def red(mytext) ; "\e[31m#{mytext}\e[0m" ; end
puts red("hello world")

然后，只有引号中的文本是有颜色的，您将返回到定期安排的节目。