# @params\["aKey"\] and multiple aKeys in request **URL:** \ **Category:** Rails\ **Created:** [March 8, 2006, 7:02pm UTC](https://www.ruby-forum.com/t/params-akey-and-multiple-akeys-in-request/78548 "2006-03-08T19:02:39Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![GSSSSbor\_SebestySSS](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/3bc359/32.png) [@GSSSSbor\_SebestySSS](https://www.ruby-forum.com/u/GSSSSbor_SebestySSS)\ **Post date:** [March 8, 2006, 7:02pm UTC](https://www.ruby-forum.com/t/params-akey-and-multiple-akeys-in-request/78548/1 "2006-03-08T19:02:39Z")
Hi, I’ve actually run into an interesting problem and no idea how to fix it. In request parameters i have multiple “url” keys like this: [url=www.abc.com](http://url=www.abc.com)&[url=cnn.com](http://url=cnn.com)&url=… But @params[:url] has only the latest value for “url” key instead of having values kept in array. So what’s next? Is there way out of this issue? Thanks, Gábor PS.: I use rails 1.0.0 and running my app in WEBrick. ---
**Author:** ![GSSSSbor\_SebestySSS](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/3bc359/32.png) [@GSSSSbor\_SebestySSS](https://www.ruby-forum.com/u/GSSSSbor_SebestySSS)\ **Post date:** [March 8, 2006, 7:15pm UTC](https://www.ruby-forum.com/t/params-akey-and-multiple-akeys-in-request/78548/2 "2006-03-08T19:15:09Z")
On 3/8/06, Gábor Sebestyén [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > In request parameters i have multiple “url” keys like this: > [url=www.abc.com](http://url=www.abc.com)&[url=cnn.com](http://url=cnn.com)&url=… > But @params[:url] has only the latest value for “url” key instead of > having values kept in array. > So what’s next? Is there way out of this issue? You’ll need different keys. Are you manually generating that URL? You may need to escape the string (I’ve used this with POST, not with GET) but you may be able to use: ?url[]=[www.abc.com](http://www.abc.com)&url[]=[www.cnn.com](http://www.cnn.com)&url[]=[www.example.com](http://www.example.com)& Which would give you an Array. @params[:url] = [‘[www.abc.com](http://www.abc.com)’, ‘[www.cnn.com](http://www.cnn.com)’, ‘[www.example.com](http://www.example.com)’ ] – Joshua ---
**Author:** ![GSSSSbor\_SebestySSS](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/3bc359/32.png) [@GSSSSbor\_SebestySSS](https://www.ruby-forum.com/u/GSSSSbor_SebestySSS)\ **Post date:** [March 9, 2006, 10:56am UTC](https://www.ruby-forum.com/t/params-akey-and-multiple-akeys-in-request/78548/3 "2006-03-09T10:56:52Z")
It’s weird. HTML standard allows using a key more than once. I checked this in irb and Ruby’s CGI::parse(…) parses my test cases in desired way and returned key - value array pairs back. myBook:~ segabor$ irb irb(main):001:0\> require ‘cgi’ =\> true irb(main):002:0\> CGI::parse(“url=a&url=b”) =\> {“url”=\>[“a”, “b”]} As far as I know RoR inherits Ruby’s cgi features and uses CGI::parse to handle incoming queries. So what make it wrong them? Gábor ---
**Author:** ![GSSSSbor\_SebestySSS](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/3bc359/32.png) [@GSSSSbor\_SebestySSS](https://www.ruby-forum.com/u/GSSSSbor_SebestySSS)\ **Post date:** [March 9, 2006, 3:43pm UTC](https://www.ruby-forum.com/t/params-akey-and-multiple-akeys-in-request/78548/4 "2006-03-09T15:43:17Z")
On 3/9/06, Josh on Rails [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > “that’s better!” > Just so you know, the order these are parsed in is not guaranteed (it > won’t necessarily be the same order as in the url). So var could end > up as “value” or “other\_value” depending on the whims of $deity > ($deity most likely being your web server in this case – appropriate > if you are using Zeus). They _usually_ are parsed in url string > order, but don’t depend on that. > Adding [] to your vars reduces ambiguity; it’s clear what you meant to > happen. It also lets you know if the variables are going to be arrays or not. var[] will always be an array (even an empty one), while var will never be. Otherwise you’d need to test ALL of your variables to see which they are. - Isaac ---
**Author:** ![GSSSSbor\_SebestySSS](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/3bc359/32.png) [@GSSSSbor\_SebestySSS](https://www.ruby-forum.com/u/GSSSSbor_SebestySSS)\ **Post date:** [March 9, 2006, 1:40pm UTC](https://www.ruby-forum.com/t/params-akey-and-multiple-akeys-in-request/78548/5 "2006-03-09T13:40:57Z")
On 3/9/06, Gábor Sebestyén [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > As far as I know RoR inherits Ruby’s cgi features and uses CGI::parse to > handle incoming queries. So what make it wrong them? Well… 1. I’m pretty sure you mean HTTP, not HTML. HTML is the Markup Language, HTTP is the Transmit Protocol. 2. If HTTP defines it as allowed, that only means that the server layer doesn’t generate an error. If it weren’t allowed in HTTP, Apache or WebBrick or Lighty would throw a “Bad Request” back at the client before Rails saw it. 3. I don’t know if, or to what extent, Rails uses CGI::parse for query string parsing. Somebody would have to look at the source code to say for sure. 4. I’m just guessing, but I imagine that Rails parses requests the way it does to reduce ambiguity. I, at least, tend to think of ?var=value&var=other\_value& as var = value “no, wait, I changed my mind” var = other\_value “that’s better!” Adding [] to your vars reduces ambiguity; it’s clear what you meant to happen. Again, I’m just guessing here, but I imagine that’s easier for the parser to parse, too. ---
**Author:** ![GSSSSbor\_SebestySSS](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/3bc359/32.png) [@GSSSSbor\_SebestySSS](https://www.ruby-forum.com/u/GSSSSbor_SebestySSS)\ **Post date:** [March 9, 2006, 7:46pm UTC](https://www.ruby-forum.com/t/params-akey-and-multiple-akeys-in-request/78548/6 "2006-03-09T19:46:19Z")
On 3/9/06, Isaac R. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > It also lets you know if the variables are going to be arrays or not. > var[] will always be an array (even an empty one), while var will > never be. Otherwise you’d need to test ALL of your variables to see > which they are. You already need to test all of your variables if you want to be sure. Since params are submitted by a client, params[:id].class could be String, Array, or Hash.