How can I match multiple occurrences with a regex in JavaScript similar to PHP's preg_match_all()?

Question

I am trying to parse url-encoded strings that are made up of key=value pairs separated by either & or &.

The following will only match the first occurrence, breaking apart the keys and values into separate result elements:

var result = mystring.match(/(?:&|&)?([^=]+)=([^&]+)/)

The results for the string '1111342=Adam%20Franco&348572=Bob%20Jones' would be:

['1111342', 'Adam%20Franco']

Using the global flag, 'g', will match all occurrences, but only return the fully matched sub-strings, not the separated keys and values:

var result = mystring.match(/(?:&|&)?([^=]+)=([^&]+)/g)

The results for the string '1111342=Adam%20Franco&348572=Bob%20Jones' would be:

['1111342=Adam%20Franco', '&348572=Bob%20Jones']

While I could split the string on & and break apart each key/value pair individually, is there any way using JavaScript's regular expression support to match multiple occurrences of the pattern /(?:&|&)?([^=]+)=([^&]+)/ similar to PHP's preg_match_all() function?

I'm aiming for some way to get results with the sub-matches separated like:

[['1111342', '348572'], ['Adam%20Franco', 'Bob%20Jones']]

or

[['1111342', 'Adam%20Franco'], ['348572', 'Bob%20Jones']]

Answer 1

Set the g modifier for a global match:

/…/g

Answer 2

You need to use the 'g' switch for a global search

var result = mystring.match(/(&|&)?([^=]+)=([^&]+)/g)

Answer 3

I would suggest an alternative regex, using sub-groups to capture name and value of the parameters individually:

var url = "http://maps.google.de/maps?f=q&source=s_q&hl=de&geocode=&q=Frankfurt+am+Main&sll=50.106047,8.679886&sspn=0.370369,0.833588&ie=UTF8&ll=50.116616,8.680573&spn=0.35972,0.833588&z=11&iwloc=addr";
var re  = /(?:\?|&(?:amp;)?)([^=]+)=?([^&]*)?/g;
var match;
while (match = re.exec(url)) {
  alert(match[1] + " = " + match[2]);
}

Outputs:

f = q
source = s_q
hl = de
geocode = undefined
q = Frankfurt+am+Main
sll = 50.106047,8.679886
sspn = 0.370369,0.833588
ie = UTF8
ll = 50.116616,8.680573
spn = 0.35972,0.833588
z = 11
iwloc = addr

Answer 4

Great!!

Thanks for sharing the code.