parameterize

parameterize :替换掉特殊字符，让它看起来像个漂亮的url，主要是根据正则表达式 ，替换掉非字母、数字及下划线的字符。。中文也将被替换掉。。。。那就没的搞了。

中文的 url 还是要自己去定义了。
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parameterize(string, sep = '-')
Replaces special characters in a string so that it may be used as part of a ‘pretty’ URL.

Examples

class Person
  def to_param
    "#{id}-#{name.parameterize}"
  end
end

@person = Person.find(1)
# => #<Person id: 1, name: "Donald E. Knuth">

<%= link_to(@person.name, person_path(@person)) %>
# => <a href="/person/1-donald-e-knuth">Donald E. Knuth</a>

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# File activesupport/lib/active_support/inflector/transliterate.rb, line 81
def parameterize(string, sep = '-')
  # replace accented chars with their ascii equivalents
  parameterized_string = transliterate(string)
  # Turn unwanted chars into the separator
  parameterized_string.gsub!(%r[^a-z0-9\-_]+/, sep)
  unless sep.nil? || sep.empty?
    re_sep = Regexp.escape(sep)
    # No more than one of the separator in a row.
    parameterized_string.gsub!(%r#{re_sep}{2,}/, sep)
    # Remove leading/trailing separator.
    parameterized_string.gsub!(%r^#{re_sep}|#{re_sep}$/, '')
  end
  parameterized_string.downcase
end