WWW::Form::UrlEncoded - parser and builder for application/x-www-form-urlencoded


    use WWW::Form::UrlEncoded qw/parse_urlencoded build_urlencoded/;
    my $query_string = "foo=bar&baz=param";
    my @params = parse_urlencoded($query_string);
    # ('foo','bar','baz','param')
    my $query_string = build_urlencoded('foo','bar','baz','param');
    # "foo=bar&baz=param";


WWW::Form::UrlEncoded provides application/x-www-form-urlencoded parser and builder. This module aims to have compatibility with other CPAN modules like HTTP::Body's urlencoded parser.

This module try to use WWW::Form::UrlEncoded::XS by default and fail to it, use WWW::Form::UrlEncoded::PP instead

Parser rules

WWW::Form::UrlEncoded parsed string in this rule.

1. Split application/x-www-form-urlencoded payload by & (U+0026) or ; (U+003B)
2. Ready empty array to store name and value
3. For each divided string, apply next steps.
1. If first character of string is ' ' (U+0020 SPACE), remove it.
2. If string has =, let name be substring from start to first =, but excluding first =, and remains to be value. If there is no strings after first =, value to be empty string "". If first = is first character of the string, let key be empty string "". If string does not have any =, all of the string to be key and value to be empty string "".
3. replace all + (U+002B) with ' ' (U+0020 SPACE).
4. unescape name and value. push them to the array.
4. return the array.

Test data

  'a=b&c=d'     => ["a","b","c","d"]
  'a=b;c=d'     => ["a","b","c","d"]
  'a=1&b=2;c=3' => ["a","1","b","2","c","3"]
  'a==b&c==d'   => ["a","=b","c","=d"]
  'a=b& c=d'    => ["a","b","c","d"]
  'a=b; c=d'    => ["a","b","c","d"]
  'a=b; c =d'   => ["a","b","c ","d"]
  'a=b;c= d '   => ["a","b","c"," d "]
  'a=b&+c=d'    => ["a","b"," c","d"]
  'a=b&+c+=d'   => ["a","b"," c ","d"]
  'a=b&c=+d+'   => ["a","b","c"," d "]
  'a=b&%20c=d'  => ["a","b"," c","d"]
  'a=b&%20c%20=d' => ["a","b"," c ","d"]
  'a=b&c=%20d%20' => ["a","b","c"," d "]
  'a&c=d'       => ["a","","c","d"]
  'a=b&=d'      => ["a","b","","d"]
  'a=b&='       => ["a","b","",""]
  '&'           => ["","","",""]
  '='           => ["",""]
  ''            => []


@param = parse_urlencoded($str:String)

parse $str and return Array that contains key-value pairs.

$param:ArrayRef = parse_urlencoded_arrayref($str:String)

parse $str and return ArrayRef that contains key-value pairs.

$string = build_urlencoded(@param)
$string = build_urlencoded(@param, $delim)
$string = build_urlencoded(\@param)
$string = build_urlencoded(\@param, $delim)
$string = build_urlencoded(\%param)
$string = build_urlencoded(\%param, $delim)

build urlencoded string from param. build_urlencoded accepts arrayref and hashref values.

  build_urlencoded( foo => 1, foo => 2);
  build_urlencoded( foo => [1,2] );
  build_urlencoded( [ foo => 1, foo => 2 ] );
  build_urlencoded( [foo => [1,2]] );
  build_urlencoded( {foo => [1,2]} );

If $delim parameter is passed, this function use it instead of using &.

$string = build_urlencoded_utf8(...)

This function is almost same as build_urlencoded. build_urlencoded_utf8 call utf8::encode for all parameters.



    If true, WWW::Form::UrlEncoded force to load WWW::Form::UrlEncoded::PP.


CPAN already has some application/x-www-form-urlencoded parser modules like these.


They does not fully compatible with WWW::Form::UrlEncoded. Handling of empty key-value and supporting separator characters are different.


Copyright (C) Masahiro Nagano.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.


Masahiro Nagano <>