将骆驼案件转换为红宝石下划线案例

Question

是否有任何将驼峰案例字符串转换为下划线分隔字符串的就绪函数？

我想是这样的：

"CamelCaseString".to_underscore  

返回 “camel_case_string”。

...

Answer 1

Rails' ActiveSupport 增加了使用以下强调的字符串：

class String 
    def underscore 
    self.gsub(/::/, '/'). 
    gsub(/([A-Z]+)([A-Z][a-z])/,'\1_\2'). 
    gsub(/([a-z\d])([A-Z])/,'\1_\2'). 
    tr("-", "_"). 
    downcase 
    end 
end 

然后，你可以做有趣的事情：

"CamelCase".underscore 
=> "camel_case" 

Answer 2

这里是如何Rails does it：

def underscore(camel_cased_word) 
    camel_cased_word.to_s.gsub(/::/, '/'). 
     gsub(/([A-Z]+)([A-Z][a-z])/,'\1_\2'). 
     gsub(/([a-z\d])([A-Z])/,'\1_\2'). 
     tr("-", "_"). 
     downcase 
    end 

Answer 3

的一行Ruby实现：

class String 
    # ruby mutation methods have the expectation to return self if a mutation occurred, nil otherwise. (see http://www.ruby-doc.org/core-1.9.3/String.html#method-i-gsub-21) 
    def to_underscore! 
    gsub!(/(.)([A-Z])/,'\1_\2') 
    downcase! 
    end 

    def to_underscore 
    dup.tap { |s| s.to_underscore! } 
    end 
end 

所以"SomeCamelCase".to_underscore # =>"some_camel_case"

Answer 4

接收器转换成蛇情况：http://rubydoc.info/gems/extlib/0.9.15/String#snake_case-instance_method

这是DataMapper的和Merb的支持库。 （http://rubygems.org/gems/extlib）

def snake_case 
    return downcase if match(/\A[A-Z]+\z/) 
    gsub(/([A-Z]+)([A-Z][a-z])/, '\1_\2'). 
    gsub(/([a-z])([A-Z])/, '\1_\2'). 
    downcase 
end 

"FooBar".snake_case   #=> "foo_bar" 
"HeadlineCNNNews".snake_case #=> "headline_cnn_news" 
"CNN".snake_case    #=> "cnn" 

Answer 5

您可以使用

"CamelCasedName".tableize.singularize 

或者只是

"CamelCasedName".underscore 

两种选择方式将产生"camel_cased_name"。您可以查看更多详情here。

Answer 6

有所谓的“下划线”，你可以使用这个目的

"CamelCaseString".underscore #=> "camel_case_string" 

的“下划线”的方法通常可以视为“camelize”

Answer 7

退房的逆的Rails的内置方法从Ruby Facets

以下情况snakecase的处理，如下所示：

"SnakeCase".snakecase   #=> "snake_case" 
"Snake-Case".snakecase  #=> "snake_case" 
"Snake Case".snakecase  #=> "snake_case" 
"Snake - Case".snakecase #=> "snake_case" 

来源：https://github.com/rubyworks/facets/blob/master/lib/core/facets/string/snakecase.rb

class String 

    # Underscore a string such that camelcase, dashes and spaces are 
    # replaced by underscores. This is the reverse of {#camelcase}, 
    # albeit not an exact inverse. 
    # 
    # "SnakeCase".snakecase   #=> "snake_case" 
    # "Snake-Case".snakecase  #=> "snake_case" 
    # "Snake Case".snakecase  #=> "snake_case" 
    # "Snake - Case".snakecase #=> "snake_case" 
    # 
    # Note, this method no longer converts `::` to `/`, in that case 
    # use the {#pathize} method instead. 

    def snakecase 
    #gsub(/::/, '/'). 
    gsub(/([A-Z]+)([A-Z][a-z])/,'\1_\2'). 
    gsub(/([a-z\d])([A-Z])/,'\1_\2'). 
    tr('-', '_'). 
    gsub(/\s/, '_'). 
    gsub(/__+/, '_'). 
    downcase 
    end 

    # 
    alias_method :underscore, :snakecase 

    # TODO: Add *separators to #snakecase, like camelcase. 

end 

Answer 8

我想这样：String类的

​​

猴子补丁。有两个或更多字母以大写字母开头。

Answer 9

短oneliner为CamelCases当你的空间还包括（如果你有一个字其间有小的出发信无法正常工作）：

a = "Test String" 
a.gsub(' ', '').underscore 

    => "test_string"