Ruby中从URL中删除参数的最优雅方式是什么？

Question

我想从URL中取出一个参数，但不知道它是哪个参数，然后重新组装URL。

我想这并不难，我自己写一些使用CGI或URI的东西，但我想这种功能已经存在了。有什么建议么？

在：

http://example.com/path?param1=one&param2=2&param3=something3 

日期：

http://example.com/path?param2=2&param3=something3 

Answer 1

的寻址创业板将很好地做到这一点;请看优秀回答者：田文。但是如果你想推出自己的产品，那么这就是如何。这段代码有高雅的唯一要求是，它隐藏丑陋的方法：

#!/usr/bin/ruby1.8 

def reject_param(url, param_to_reject) 
    # Regex from RFC3986 
    url_regex = %r"^(([^:/?#]+):)?(//([^/?#]*))?([^?#]*)(\?([^#]*))?(#(.*))?$" 
    raise "Not a url: #{url}" unless url =~ url_regex 
    scheme_plus_punctuation = $1 
    authority_with_punctuation = $3 
    path = $5 
    query = $7 
    fragment = $9 
    query = query.split('&').reject do |param| 
    param_name = param.split(/[=;]/).first 
    param_name == param_to_reject 
    end.join('&') 
    [scheme_plus_punctuation, authority_with_punctuation, path, '?', query, fragment].join 
end 

url = "http://example.com/path?param1=one&param2=2&param3=something3" 
p url 
p reject_param(url, 'param2') 

# => "http://example.com/path?param1=one&param2=2&param3=something3" 
# => "http://example.com/path?param1=one&param3=something3" 

Answer 2

我想出了这样的事情

def uri_remove_param(uri, params = nil) 
    return uri unless params 
    params = Array(params) 
    uri_parsed = URI.parse(uri) 
    return uri unless uri_parsed.query 
    escaped = uri_parsed.query.grep(/&/).size > 0 
    new_params = uri_parsed.query.gsub(/&/, '&').split('&').reject { |q| params.include?(q.split('=').first) } 
    uri = uri.split('?').first 
    amp = escaped ? '&' : '&' 
    "#{uri}?#{new_params.join(amp)}" 
end 

Answer 3

也许题外话，但任何人谁是一个小试图在rails应用程序的上下文中执行此操作，您只需执行以下操作：

url_for(params.except(:name_of_param_to_delete)) 

NB在rails v2.3.9中测试。

Answer 4

我更喜欢使用：

require 'addressable/uri' 

uri = Addressable::URI.parse('http://example.com/path?param1=one&param2=2&param3=something3') 

params = uri.query_values #=> {"param1"=>"one", "param2"=>"2", "param3"=>"something3"} 
params.delete('param1') #=> "one" 
uri.query_values = params #=> {"param2"=>"2", "param3"=>"something3"} 

uri.to_s #=> "http://example.com/path?param2=2&param3=something3" 

Answer 5

如果你不希望包括一个额外的宝石，如果你不想让讨厌的正则表达式，这里是我的首选方式：

require 'cgi' 
require 'uri' 

url = "http://example.com/path?param1=one&param2=2&param3=something3" 

uri = URI(url) #=> #<URI::HTTP:0x007fbe25141a78 URL:http://example.com/path?param1=one&param2=2&param3=something3> 
params = CGI.parse(uri.query || "") #=> {"param1"=>["one"], "param2"=>["2"], "param3"=>["something3"]} 
params.delete('param1') #=> ["one"] 
uri.query = URI.encode_www_form(params) #=> "param2=2&param3=something3" 

uri.to_s #=> "http://example.com/path?param2=2&param3=something3" 

Answer 6

一行应该是足够的：

url.sub(/\?param_to_remove=[^&]*/, '?').sub(/\&param_to_remove=[^&]*/, '').sub(/\?$/,'')