URL encoding

From Rosetta Code
Revision as of 03:40, 15 November 2014 by Peak (talk | contribs) (jq)
Task
URL encoding
You are encouraged to solve this task according to the task description, using any language you may know.

The task is to provide a function or mechanism to convert a provided string into URL encoding representation.

In URL encoding, special characters, control characters and extended characters are converted into a percent symbol followed by a two digit hexadecimal code, So a space character encodes into %20 within the string.

For the purposes of this task, every character except 0-9, A-Z and a-z requires conversion, so the following characters all require conversion by default:

  • ASCII control codes (Character ranges 00-1F hex (0-31 decimal) and 7F (127 decimal).
  • ASCII symbols (Character ranges 32-47 decimal (20-2F hex))
  • ASCII symbols (Character ranges 58-64 decimal (3A-40 hex))
  • ASCII symbols (Character ranges 91-96 decimal (5B-60 hex))
  • ASCII symbols (Character ranges 123-126 decimal (7B-7E hex))
  • Extended characters with character codes of 128 decimal (80 hex) and above.

Example

The string "http://foo bar/" would be encoded as "http%3A%2F%2Ffoo%20bar%2F".

Variations

  • Lowercase escapes are legal, as in "http%3a%2f%2ffoo%20bar%2f".
  • Some standards give different rules: RFC 3986, Uniform Resource Identifier (URI): Generic Syntax, section 2.3, says that "-._~" should not be encoded. HTML 5, section 4.10.22.5 URL-encoded form data, says to preserve "-._*", and to encode space " " to "+". The options below provide for utilization of an exception string, enabling preservation (non encoding) of particular characters to meet specific standards.

Options

It is permissible to use an exception string (containing a set of symbols that do not need to be converted). However, this is an optional feature and is not a requirement of this task.

See also

URL decoding

Ada

Library: AWS

<lang Ada>with AWS.URL; with Ada.Text_IO; use Ada.Text_IO; procedure Encode is

  Normal : constant String := "http://foo bar/";

begin

  Put_Line (AWS.URL.Encode (Normal));

end Encode;</lang> Output:

http%3A%2F%2Ffoo%20bar%2F

AutoHotkey

<lang AutoHotkey>MsgBox, % UriEncode("http://foo bar/")

Modified from http://goo.gl/0a0iJq

UriEncode(Uri) { VarSetCapacity(Var, StrPut(Uri, "UTF-8"), 0) StrPut(Uri, &Var, "UTF-8") f := A_FormatInteger SetFormat, IntegerFast, H While Code := NumGet(Var, A_Index - 1, "UChar") If (Code >= 0x30 && Code <= 0x39 ; 0-9 || Code >= 0x41 && Code <= 0x5A ; A-Z || Code >= 0x61 && Code <= 0x7A) ; a-z Res .= Chr(Code) Else Res .= "%" . SubStr(Code + 0x100, -1) SetFormat, IntegerFast, %f% Return, Res }</lang>

AWK

<lang awk>BEGIN { for (i = 0; i <= 255; i++) ord[sprintf("%c", i)] = i }

  1. Encode string with application/x-www-form-urlencoded escapes.

function escape(str, c, len, res) { len = length(str) res = "" for (i = 1; i <= len; i++) { c = substr(str, i, 1); if (c ~ /[0-9A-Za-z]/) #if (c ~ /[-._*0-9A-Za-z]/) res = res c #else if (c == " ") # res = res "+" else res = res "%" sprintf("%02X", ord[c]) } return res }

  1. Escape every line of input.

{ print escape($0) }</lang>

The array ord[] uses idea from Character codes#AWK.

To follow the rules for HTML 5, uncomment the two lines that convert " " to "+", and use the regular expression that preserves "-._*".

BBC BASIC

<lang bbcbasic> PRINT FNurlencode("http://foo bar/")

     END
     
     DEF FNurlencode(url$)
     LOCAL c%, i%
     WHILE i% < LEN(url$)
       i% += 1
       c% = ASCMID$(url$, i%)
       IF c%<&30 OR c%>&7A OR c%>&39 AND c%<&41 OR c%>&5A AND c%<&61 THEN
         url$ = LEFT$(url$,i%-1) + "%" + RIGHT$("0"+STR$~c%,2) + MID$(url$,i%+1)
       ENDIF
     ENDWHILE
     = url$</lang>

Output:

http%3A%2F%2Ffoo%20bar%2F

Bracmat

<lang bracmat>( ( encode

     =   encoded exceptions octet string
       .     !arg:(?exceptions.?string)
           & :?encoded
           & @( !string
              :   ?
                  ( %@?octet ?
                  &     !encoded
                        (   !octet
                          : ( ~<0:~>9
                            | ~<A:~>Z
                            | ~<a:~>z
                            )
                        |   @(!exceptions:? !octet ?)
                          & !octet
                        | "%" d2x$(asc$!octet)
                        )
                    : ?encoded
                  & ~
                  )
              )
         | str$!encoded
     )
   & out$"without exceptions:

"

   & out$(encode$(."http://foo bar/"))
   & out$(encode$(."mailto:Ivan"))
   & out$(encode$(."Aim <ivan.aim@email.com>"))
   & out$(encode$(."mailto:Irma"))
   & out$(encode$(."User <irma.user@mail.com>"))
   & out$(encode$(."http://foo.bar.com/~user-name/_subdir/*~.html"))
   & out$"

with RFC 3986 rules: "

   & out$(encode$("-._~"."http://foo bar/"))
   & out$(encode$("-._~"."mailto:Ivan"))
   & out$(encode$("-._~"."Aim <ivan.aim@email.com>"))
   & out$(encode$("-._~"."mailto:Irma"))
   & out$(encode$("-._~"."User <irma.user@mail.com>"))
   & out$(encode$("-._~"."http://foo.bar.com/~user-name/_subdir/*~.html"))

); </lang> Output:

without exceptions:

http%3A%2F%2Ffoo%20bar%2F
mailto%3AIvan
Aim%20%3Civan%2Eaim%40email%2Ecom%3E
mailto%3AIrma
User%20%3Cirma%2Euser%40mail%2Ecom%3E
http%3A%2F%2Ffoo%2Ebar%2Ecom%2F%7Euser%2Dname%2F%5Fsubdir%2F%2A%7E%2Ehtml

with RFC 3986 rules:

http%3A%2F%2Ffoo%20bar%2F
mailto%3AIvan
Aim%20%3Civan.aim%40email.com%3E
mailto%3AIrma
User%20%3Cirma.user%40mail.com%3E
http%3A%2F%2Ffoo.bar.com%2F~user-name%2F_subdir%2F%2A~.html

C

<lang c>#include <stdio.h>

  1. include <ctype.h>

char rfc3986[256] = {0}; char html5[256] = {0};

/* caller responsible for memory */ void encode(unsigned char *s, char *enc, char *tb) { for (; *s; s++) { if (tb[*s]) sprintf(enc, "%c", tb[*s]); else sprintf(enc, "%%%02X", *s); while (*++enc); } }

int main() { unsigned char url[] = "http://foo bar/"; char enc[sizeof(url) * 3];

int i; for (i = 0; i < 256; i++) { rfc3986[i] = isalnum(i)||i == '~'||i == '-'||i == '.'||i == '_' ? i : 0; html5[i] = isalnum(i)||i == '*'||i == '-'||i == '.'||i == '_' ? i : (i == ' ') ? '+' : 0; }

encode(url, enc, rfc3986); puts(enc);

return 0; }</lang>

C++

using Qt 4.6 as a library <lang cpp>#include <QByteArray>

  1. include <iostream>

int main( ) {

  QByteArray text ( "http://foo bar/" ) ;
  QByteArray encoded( text.toPercentEncoding( ) ) ;
  std::cout << encoded.data( ) << '\n' ;
  return 0 ;

}</lang> Output:

http%3A%2F%2Ffoo%20bar%2F

C#

<lang c sharp>using System;

namespace URLEncode {

   internal class Program
   {
       private static void Main(string[] args)
       {
           Console.WriteLine(Encode("http://foo bar/"));
       }
       private static string Encode(string uri)
       {
           return Uri.EscapeDataString(uri);
       }
   }

}</lang>

Output

http%3A%2F%2Ffoo%20bar%2F

Clojure

Using Java's URLEncoder: <lang clojure>(import 'java.net.URLEncoder) (URLEncoder/encode "http://foo bar/" "UTF-8")</lang>

Output:
"http%3A%2F%2Ffoo+bar%2F"

D

<lang d>import std.stdio, std.uri;

void main() {

   writeln(encodeComponent("http://foo bar/"));

}</lang>

http%3A%2F%2Ffoo%20bar%2F

Erlang

Built in

33> http_uri:encode("http://foo bar/").
"http%3A%2F%2Ffoo%20bar%2F"

F#

<lang fsharp>open System

[<EntryPoint>] let main args =

   printfn "%s" (Uri.EscapeDataString(args.[0]))
   0</lang>

Output

>URLencoding.exe "http://foo bar/"
http%3A%2F%2Ffoo%20bar%2F

Go

<lang go>package main

import (

   "fmt"
   "net/url"

)

func main() {

   fmt.Println(url.QueryEscape("http://foo bar/"))

}</lang> Output:

http%3A%2F%2Ffoo+bar%2F

Icon and Unicon

<lang Icon>link hexcvt

procedure main() write("text = ",image(u := "http://foo bar/")) write("encoded = ",image(ue := encodeURL(u))) end

procedure encodeURL(s) #: encode data for inclusion in a URL/URI static en initial { # build lookup table for everything

  en := table()
  every en[c := !string(~(&digits++&letters))] := "%"||hexstring(ord(c),2)
  every /en[c := !string(&cset)] := c
  }

every (c := "") ||:= en[!s] # re-encode everything return c end </lang>

hexcvt provides hexstring

Output:
text    = "http://foo bar/"
encoded = "http%3A%2F%2Ffoo%20bar%2F"

J

J has a urlencode in the gethttp package, but this task requires that all non-alphanumeric characters be encoded.

Here's an implementation that does that:

<lang j>require'strings convert' urlencode=: rplc&((#~2|_1 47 57 64 90 96 122 I.i.@#)a.;"_1'%',.hfd i.#a.)</lang>

Example use:

<lang j> urlencode 'http://foo bar/' http%3A%2F%2Ffoo%20bar%2F</lang>

Java

The built-in URLEncoder in Java converts the space " " into a plus-sign "+" instead of "%20": <lang java>import java.io.UnsupportedEncodingException; import java.net.URLEncoder;

public class Main {

   public static void main(String[] args) throws UnsupportedEncodingException
   {
       String normal = "http://foo bar/";
       String encoded = URLEncoder.encode(normal, "utf-8");
       System.out.println(encoded);
   }

}</lang>

Output:

http%3A%2F%2Ffoo+bar%2F

JavaScript

Confusingly, there are 3 different URI encoding functions in JavaScript: escape(), encodeURI(), and encodeURIComponent(). Each of them encodes a different set of characters. See this article and this article for more information and comparisons. <lang javascript>var normal = 'http://foo/bar/'; var encoded = encodeURIComponent(normal);</lang>

jq

jq has just one built-in function, @uri, for "percent-encoding"; it maps all reserved URI characters to a %xx sequence, for example: <lang jq>"http://foo bar/" | @uri

  1. => "http%3A%2F%2Ffoo%20bar%2F" # as required</lang>

To check that each character in "-._~" is unaltered by the encoding: <lang jq>"-._~" | . == @uri

  1. => true</lang>

Lasso

<lang Lasso>bytes('http://foo bar/') -> encodeurl</lang> -> http%3A%2F%2Ffoo%20bar%2F

Liberty BASIC

<lang lb>

   dim lookUp$( 256)
   for i =0 to 256
       lookUp$( i) ="%" +dechex$( i)
   next i
   string$ ="http://foo bar/"
   print "Supplied string '"; string$; "'"
   print "As URL          '"; url$( string$); "'"
   end

function url$( i$)

   for j =1 to len( i$)
       c$ =mid$( i$, j, 1)
       if instr( "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz", c$) then
           url$ =url$ +c$ 
       else
           url$ =url$ +lookUp$( asc( c$))
       end if
   next j

end function </lang>

 Supplied string 'http://foo bar/'
 As URL 'http%3A%2F%2Ffoo%20bar%2F'

NetRexx

<lang NetRexx>/* NetRexx */ options replace format comments java crossref symbols nobinary

/* -------------------------------------------------------------------------- */

 testcase()
 say
 say 'RFC3986'
 testcase('RFC3986')
 say
 say 'HTML5'
 testcase('HTML5')
 say
 return

/* -------------------------------------------------------------------------- */ method encode(url, varn) public static

 variation = varn.upper 
 opts = 
 opts['RFC3986'] = '-._~'
 opts['HTML5']   = '-._*'
 rp = 
 loop while url.length > 0
   parse url tc +1 url
   select
     when tc.datatype('A') then do
       rp = rp || tc
       end
     when tc == ' ' then do
       if variation = 'HTML5' then
         rp = rp || '+'
       else
         rp = rp || '%' || tc.c2x
       end
     otherwise do
       if opts[variation].pos(tc) > 0 then do
         rp = rp || tc
         end
       else do
         rp = rp || '%' || tc.c2x
         end
       end
     end
   end
 return rp

/* -------------------------------------------------------------------------- */ method testcase(variation = ) public static

 url = [ -
     'http://foo bar/' -
   , 'mailto:"Ivan Aim" <ivan.aim@email.com>' -
   , 'mailto:"Irma User" <irma.user@mail.com>' -
   , 'http://foo.bar.com/~user-name/_subdir/*~.html' -
   ]
 loop i_ = 0 to url.length - 1
   say url[i_]
   say encode(url[i_], variation)
   end i_
 return

</lang>

Output:

http://foo bar/ 
http%3A%2F%2Ffoo%20bar%2F 
mailto:"Ivan Aim" <ivan.aim@email.com> 
mailto%3A%22Ivan%20Aim%22%20%3Civan%2Eaim%40email%2Ecom%3E 
mailto:"Irma User" <irma.user@mail.com> 
mailto%3A%22Irma%20User%22%20%3Cirma%2Euser%40mail%2Ecom%3E 
http://foo.bar.com/~user-name/_subdir/*~.html 
http%3A%2F%2Ffoo%2Ebar%2Ecom%2F%7Euser%2Dname%2F%5Fsubdir%2F%2A%7E%2Ehtml 
 
RFC3986 
http://foo bar/ 
http%3A%2F%2Ffoo%20bar%2F 
mailto:"Ivan Aim" <ivan.aim@email.com> 
mailto%3A%22Ivan%20Aim%22%20%3Civan.aim%40email.com%3E 
mailto:"Irma User" <irma.user@mail.com> 
mailto%3A%22Irma%20User%22%20%3Cirma.user%40mail.com%3E 
http://foo.bar.com/~user-name/_subdir/*~.html 
http%3A%2F%2Ffoo.bar.com%2F~user-name%2F_subdir%2F%2A~.html 
 
HTML5 
http://foo bar/ 
http%3A%2F%2Ffoo+bar%2F 
mailto:"Ivan Aim" <ivan.aim@email.com> 
mailto%3A%22Ivan+Aim%22+%3Civan.aim%40email.com%3E 
mailto:"Irma User" <irma.user@mail.com> 
mailto%3A%22Irma+User%22+%3Cirma.user%40mail.com%3E 
http://foo.bar.com/~user-name/_subdir/*~.html 
http%3A%2F%2Ffoo.bar.com%2F%7Euser-name%2F_subdir%2F*%7E.html

Maple

<lang maple>URL:-Escape("http://foo bar/");</lang>

Output:

"http%3A%2F%2Ffoo%20bar%2F"

Mathematica

<lang mathematica>URLEncoding[url_] :=

StringReplace[url, 
 x : Except[
    Join[CharacterRange["0", "9"], CharacterRange["a", "z"], 
     CharacterRange["A", "Z"]]] :> 
  StringJoin[("%" ~~ #) & /@ 
    IntegerString[ToCharacterCode[x, "UTF8"], 16]]]</lang>

Example use:

<lang mathematica>URLEncoding["http://foo bar/"]</lang>

Output:

http%3a%2f%2ffoo%20bar%2f

MATLAB / Octave

<lang MATLAB>function u = urlencoding(s) u = ; for k = 1:length(s), if isalnum(s(k)) u(end+1) = s(k); else u=[u,'%',dec2hex(s(k)+0)]; end; end end</lang> Usage:

octave:3> urlencoding('http://foo bar/')
ans = http%3A%2F%2Ffoo%20bar%2F

NewLISP

<lang NewLISP>;; simple encoder

(source http://www.newlisp.org/index.cgi?page=Code_Snippets)

(define (url-encode str)

 (replace {([^a-zA-Z0-9])} str (format "%%%2X" (char $1)) 0))

(url-encode "http://foo bar/")</lang>

Nimrod

<lang nimrod>import cgi

echo urlEncode("http://foo/bar/")</lang>

Objeck

<lang objeck> use FastCgi;

bundle Default {

 class UrlEncode {
   function : Main(args : String[]) ~ Nil {
     url := "http://foo bar/";
     UrlUtility->Encode(url)->PrintLine();
   }
 }

} </lang>

Objective-C

Works with: Cocoa version Mac OS X 10.3+

<lang objc>NSString *normal = @"http://foo bar/"; NSString *encoded = [normal stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]; NSLog(@"%@", encoded);</lang>

The Core Foundation function CFURLCreateStringByAddingPercentEscapes() provides more options.

OCaml

Using the library ocamlnet from the interactive loop:

<lang ocaml>$ ocaml

  1. #use "topfind";;
  2. #require "netstring";;
  1. Netencoding.Url.encode "http://foo bar/" ;;

- : string = "http%3A%2F%2Ffoo+bar%2F"</lang>

ooRexx

The solution shown at Rexx is a valid ooRexx program.

Perl

<lang perl>sub urlencode {

   my $s = shift;
   $s =~ s/([^-A-Za-z0-9_.!~*'() ])/sprintf("%%%02X", ord($1))/eg;
   $s =~ tr/ /+/;
   return $s;

}

print urlencode('http://foo bar/')."\n"; </lang>

Output:

http%3A%2F%2Ffoo+bar%2F

<lang perl>use URI::Escape;

my $s = 'http://foo/bar/'; print uri_escape($s);</lang>

Use standard CGI module: <lang perl>use 5.10.0; use CGI;

my $s = 'http://foo/bar/'; say $s = CGI::escape($s); say $s = CGI::unescape($s);</lang>

Perl 6

<lang perl6>my $url = 'http://foo bar/';

say $url.subst(/<-[ A..Z a..z 0..9 ]>/, *.ord.fmt("%%%02X"), :g);</lang>

Output:

http%3A%2F%2Ffoo%20bar%2F

PHP

<lang php><?php $s = 'http://foo/bar/'; $s = rawurlencode($s); ?></lang> There is also urlencode(), which also encodes spaces as "+" signs

PicoLisp

<lang PicoLisp>(de urlEncodeTooMuch (Str)

  (pack
     (mapcar
        '((C)
           (if (or (>= "9" C "0") (>= "Z" (uppc C) "A"))
              C
              (list '% (hex (char C))) ) )
        (chop Str) ) ) )</lang>

Test:

: (urlEncodeTooMuch "http://foo bar/")
-> "http%3A%2F%2Ffoo%20bar%2F"

PureBasic

<lang PureBasic>URL$ = URLEncoder("http://foo bar/")</lang>

Python

<lang python>import urllib s = 'http://foo/bar/' s = urllib.quote(s)</lang> There is also urllib.quote_plus(), which also encodes spaces as "+" signs

R

R has a built-in

<lang R>URLencode("http://foo bar/")</lang>

function, but it doesn't fully follow RFC guidelines, so we have to use another R package to accomplish the task:

<lang R> library(RCurl) curlEscape("http://foo bar/") </lang>


Racket

<lang racket>

  1. lang racket

(require net/uri-codec) (uri-encode "http://foo bar/") </lang>

REALbasic

Using the built-in encoding method, which doesn't permit exceptions: <lang vb>

 Dim URL As String = "http://foo bar/"
 URL = EncodeURLComponent(URL)
 Print(URL)

</lang>

With exceptions: <lang vb> Function URLEncode(URL As String, Exceptions As String = "") As String

 For i As Integer = 0 To 255
   If InStr(Exceptions, Chr(i)) > 0 Then Continue For i
   Dim char As String = Chr(127) + Right("00" + Hex(i), 2)
   URL = ReplaceAll(URL, Chr(i), char)
   If i = 47 Then i = 57
   If i = 64 Then i = 90
   If i = 96 Then i = 122
   If i = 126 Then i = 128
 Next
 URL = ReplaceAll(URL, Chr(127), "%")
 Return URL

End Function </lang>


REXX

version 1

<lang REXX>/* Rexx */ do

 call testcase
 say
 say RFC3986
 call testcase RFC3986
 say
 say HTML5
 call testcase HTML5
 say
 return

end exit

/* -------------------------------------------------------------------------- */ encode: procedure do

 parse arg url, varn .
 parse upper var varn variation 
 drop RFC3986 HTML5
 opts. = 
 opts.RFC3986 = '-._~'
 opts.HTML5   = '-._*'
 rp = 
 do while length(url) > 0
   parse var url tc +1 url
   select
     when datatype(tc, 'A') then do
       rp = rp || tc
       end
     when tc == ' ' then do
       if variation = HTML5 then
         rp = rp || '+'
       else
         rp = rp || '%' || c2x(tc)
       end
     otherwise do
       if pos(tc, opts.variation) > 0 then do
         rp = rp || tc
         end
       else do
         rp = rp || '%' || c2x(tc)
         end
       end
     end
   end
 return rp

end exit

/* -------------------------------------------------------------------------- */ testcase: procedure do

 parse arg variation
 X = 0
 url. = 
 X = X + 1; url.0 = X; url.X = 'http://foo bar/'
 X = X + 1; url.0 = X; url.X = 'mailto:"Ivan Aim" <ivan.aim@email.com>'
 X = X + 1; url.0 = X; url.X = 'mailto:"Irma User" <irma.user@mail.com>'
 X = X + 1; url.0 = X; url.X = 'http://foo.bar.com/~user-name/_subdir/*~.html'
 do i_ = 1 to url.0
   say url.i_
   say encode(url.i_, variation)
   end i_
 return

end </lang>

Output:
http://foo bar/
http%3A%2F%2Ffoo%20bar%2F
mailto:"Ivan Aim" <ivan.aim@email.com>
mailto%3A%22Ivan%20Aim%22%20%3Civan%2Eaim%40email%2Ecom%3E
mailto:"Irma User" <irma.user@mail.com>
mailto%3A%22Irma%20User%22%20%3Cirma%2Euser%40mail%2Ecom%3E
http://foo.bar.com/~user-name/_subdir/*~.html
http%3A%2F%2Ffoo%2Ebar%2Ecom%2F%7Euser%2Dname%2F%5Fsubdir%2F%2A%7E%2Ehtml

RFC3986
http://foo bar/
http%3A%2F%2Ffoo%20bar%2F
mailto:"Ivan Aim" <ivan.aim@email.com>
mailto%3A%22Ivan%20Aim%22%20%3Civan.aim%40email.com%3E
mailto:"Irma User" <irma.user@mail.com>
mailto%3A%22Irma%20User%22%20%3Cirma.user%40mail.com%3E
http://foo.bar.com/~user-name/_subdir/*~.html
http%3A%2F%2Ffoo.bar.com%2F~user-name%2F_subdir%2F%2A~.html

HTML5
http://foo bar/
http%3A%2F%2Ffoo+bar%2F
mailto:"Ivan Aim" <ivan.aim@email.com>
mailto%3A%22Ivan+Aim%22+%3Civan.aim%40email.com%3E
mailto:"Irma User" <irma.user@mail.com>
mailto%3A%22Irma+User%22+%3Cirma.user%40mail.com%3E
http://foo.bar.com/~user-name/_subdir/*~.html
http%3A%2F%2Ffoo.bar.com%2F%7Euser-name%2F_subdir%2F*%7E.html

version 2

<lang rexx>/*REXX pgm encodes an URL text, blanks──►+, preserves -._* and -._~ */ url.1 = 'http://foo bar/' url.2 = 'mailto:"Ivan Aim" <ivan.aim@email.com>' url.3 = 'mailto:"Irma User" <irma.user@mail.com>' url.4 = 'http://foo.bar.com/~user-name/_subdir/*~.html' URLs = 4

            do j=1  for URLs;     say
            say url.j
            say URLencode(url.j)
            end   /*j*/

exit /*stick a fork in it, we're done.*/ /*──────────────────────────────────URLENCODE subroutine────────────────*/ URLencode: procedure; parse arg yyy; t1= '-._~' ; skip=0

                                      t2= '-._*' ;               z=
         do k=1  for length(yyy);     _=substr(yyy,k,1) /*pickoff 1char*/
         if skip\==0  then do                           /*skip t1 | t2?*/
                           skip=skip-1                  /*skip a char. */
                           iterate
                           end
           select
           when datatype(_,'A')       then z=z || _     /*alphanumeric?*/
           when _==' '                then z=z'+'       /*is a blank ? */
           when substr(yyy,k,4)==t1 |,                  /*t1  or  t2 ? */
                substr(yyy,k,4)==t2   then do;  skip=3  /*skip 3 chars.*/
                                           z=z || substr(yyy,k,4)
                                           end
           otherwise                       z=z'%'c2x(_) /*special char.*/
           end   /*select*/
         end     /*k*/

return z</lang> output when using the default input

http://foo bar/
http%3A%2F%2Ffoo+bar%2F

mailto:"Ivan Aim" <ivan.aim@email.com>
mailto%3A%22Ivan+Aim%22+%3Civan%2Eaim%40email%2Ecom%3E

mailto:"Irma User" <irma.user@mail.com>
mailto%3A%22Irma+User%22+%3Cirma%2Euser%40mail%2Ecom%3E

http://foo.bar.com/~user-name/_subdir/*~.html
http%3A%2F%2Ffoo%2Ebar%2Ecom%2F%7Euser%2Dname%2F%5Fsubdir%2F%2A%7E%2Ehtml

Ruby

CGI.escape encodes all characters except '-.0-9A-Z_a-z'.

<lang ruby>require 'cgi' puts CGI.escape("http://foo bar/").gsub("+", "%20")

  1. => "http%3A%2F%2Ffoo%20bar%2F"</lang>

Programs should not call URI.escape (alias URI.encode), because it fails to encode some characters. URI.escape is obsolete since Ruby 1.9.2.

URI.encode_www_form_component is a new method from Ruby 1.9.2. It obeys HTML 5 and encodes all characters except '-.0-9A-Z_a-z' and '*'.

Works with: Ruby version 1.9.2

<lang ruby>require 'uri' puts URI.encode_www_form_component("http://foo bar/").gsub("+", "%20")

  1. => "http%3A%2F%2Ffoo%20bar%2F"</lang>

Run BASIC

<lang runbasic>urlIn$ = "http://foo bar/"

for i = 1 to len(urlIn$)

 a$ = mid$(urlIn$,i,1)
 if (a$ >= "0" and a$ <= "9") _
 or (a$ >= "A" and a$ <= "Z") _
 or (a$ >= "a" and a$ <= "z") then url$ = url$ + a$ else url$ = url$ + "%"+dechex$(asc(a$))

next i print urlIn$;" -> ";url$</lang>

http://foo bar/ -> http%3A%2F%2Ffoo%20bar%2F

Scala

Library: Scala
<lang scala>import java.net.{URLDecoder, URLEncoder}

import scala.compat.Platform.currentTime

object UrlCoded extends App {

 val original = """http://foo bar/"""
 val encoded: String = URLEncoder.encode(original, "UTF-8")
 assert(encoded == "http%3A%2F%2Ffoo+bar%2F", s"Original: $original not properly encoded: $encoded")
 val percentEncoding = encoded.replace("+", "%20")
 assert(percentEncoding == "http%3A%2F%2Ffoo%20bar%2F", s"Original: $original not properly percent-encoded: $percentEncoding")
 assert(URLDecoder.decode(encoded, "UTF-8") == URLDecoder.decode(percentEncoding, "UTF-8"))
 println(s"Successfully completed without errors. [total ${currentTime - executionStart} ms]")

}</lang>

Seed7

The library encoding.s7i defines functions to handle URL respectively percent encoding. The function toPercentEncoded encodes every character except 0-9, A-Z, a-z and the characters '-', '.', '_', '~'. The function toUrlEncoded works like toPercentEncoded and additionally encodes a space with '+'. Both functions work for byte sequences (characters beyond '\255\' raise the exception RANGE_ERROR). To encode Unicode characters it is necessary to convert them to UTF-8 with striToUtf8 before.<lang seed7>$ include "seed7_05.s7i";

 include "encoding.s7i";

const proc: main is func

 begin
   writeln(toPercentEncoded("http://foo bar/"));
   writeln(toUrlEncoded("http://foo bar/"));
end func;</lang>
Output:
http%3A%2F%2Ffoo%20bar%2F
http%3A%2F%2Ffoo+bar%2F

Tcl

<lang tcl># Encode all except "unreserved" characters; use UTF-8 for extended chars.

  1. See http://tools.ietf.org/html/rfc3986 §2.4 and §2.5

proc urlEncode {str} {

   set uStr [encoding convertto utf-8 $str]
   set chRE {[^-A-Za-z0-9._~\n]};		# Newline is special case!
   set replacement {%[format "%02X" [scan "\\\0" "%c"]]}
   return [string map {"\n" "%0A"} [subst [regsub -all $chRE $uStr $replacement]]]

}</lang> Demonstrating: <lang tcl>puts [urlEncode "http://foo bar/"]</lang> Output:

http%3A%2F%2Ffoo%20bar%2F%E2%82%AC

TUSCRIPT

<lang tuscript> $$ MODE TUSCRIPT text="http://foo bar/" BUILD S_TABLE spez_char="::>/:</::<%:" spez_char=STRINGS (text,spez_char) LOOP/CLEAR c=spez_char c=ENCODE(c,hex),c=concat("%",c),spez_char=APPEND(spez_char,c) ENDLOOP url_encoded=SUBSTITUTE(text,spez_char,0,0,spez_char) print "text: ", text PRINT "encoded: ", url_encoded </lang> Output:

text:    http://foo bar/
encoded: http%3A%2F%2Ffoo%20bar%2F

UNIX Shell

Works with: bash
Works with: ksh

<lang bash>function urlencode { typeset decoded=$1 encoded= rest= c= typeset rest2= bug='rest2=${rest}'

if [[ -z ${BASH_VERSION} ]]; then # bug /usr/bin/sh HP-UX 11.00 typeset _decoded='xyz%26xyz' rest="${_decoded#?}" c="${_decoded%%${rest}}" if (( ${#c} != 1 )); then typeset qm='????????????????????????????????????????????????????????????????????????' typeset bug='(( ${#rest} > 0 )) && typeset -L${#rest} rest2="${qm}" || rest2=${rest}' fi fi

rest="${decoded#?}" eval ${bug} c="${decoded%%${rest2}}" decoded="${rest}"

while [[ -n ${c} ]]; do case ${c} in [-a-zA-z0-9.]) ;; ' ') c='+' ;; *) c=$(printf "%%%02X" "'$c") ;; esac

encoded="${encoded}${c}"

rest="${decoded#?}" eval ${bug} c="${decoded%%${rest2}}" decoded="${rest}" done

if [[ -n ${BASH_VERSION:-} ]]; then \echo -E "${encoded}" else print -r -- "${encoded}" fi } </lang>

XPL0

<lang XPL0>code Text=12; string 0; \use zero-terminated strings

func Encode(S0); \Encode URL string and return its address char S0; char HD, S1(80); \BEWARE: very temporary string space returned int C, I, J; [HD:= "0123456789ABCDEF"; \hex digits I:= 0; J:= 0; repeat C:= S0(I); I:= I+1;

       if C>=^0 & C<=^9 ! C>=^A & C<=^Z ! C>=^a & C<=^z ! C=0
       then    [S1(J):= C;  J:= J+1]           \simply pass char to S1
       else    [S1(J):= ^%;  J:= J+1;          \encode char into S1
                S1(J):= HD(C>>4);  J:= J+1;
                S1(J):= HD(C&$0F); J:= J+1;
               ];

until C=0; return S1; ];

Text(0, Encode("http://foo bar/"))</lang>

Output:

http%3A%2F%2Ffoo%20bar%2F

zkl

Using lib cURL: <lang zkl>var CURL=Import("zklCurl"); CURL.urlEncode("http://foo bar/") //--> "http%3A%2F%2Ffoo%20bar%2F"</lang>