Standard URL encode function?

Question

Is there a Delphi equivalent of this .net\'s method:

Url.UrlEncode()

Note
I haven\'t worked with Delphi for several years now. As I

Answer 1

I have made my own function. It converts spaces to %20, not to plus sign. It was needed to convert local file path to path for browser (with file:/// prefix). The most important is it handles UTF-8 strings. It was inspired by Radek Hladik's solution above.

function URLEncode(s: string): string;
var
  i: integer;
  source: PAnsiChar;
begin
  result := '';
  source := pansichar(s);
  for i := 1 to length(source) do
    if not (source[i - 1] in ['A'..'Z', 'a'..'z', '0'..'9', '-', '_', '~', '.', ':', '/']) then
      result := result + '%' + inttohex(ord(source[i - 1]), 2)
    else
      result := result + source[i - 1];
end;       

Answer 2

Another simple way of doing this is to use the HTTPEncode function in the HTTPApp unit - very roughly

Uses 
  HTTPApp;

function URLEncode(const s : string) : string;
begin
  result := HTTPEncode(s);
end

---

HTTPEncode is deprecated in Delphi 10.3 - 'Use TNetEncoding.URL.Decode'

Uses
  NetEncoding;

function URLEncode(const s : string) : string;
begin
  result := TNetEncoding.URL.Encode(s);
end

Answer 3

Another option, is to use the Synapse library which has a simple URL encoding method (as well as many others) in the SynaCode unit.

uses
  SynaCode;
..
begin
  s := EncodeUrl( str );
//
  s := DecodeUrl( str );
end;

Answer 4

I was also facing the same issue (Delphi 4).

I resolved the issue using below mentioned function:

function fnstUrlEncodeUTF8(stInput : widestring) : string;
  const
    hex : array[0..255] of string = (
     '%00', '%01', '%02', '%03', '%04', '%05', '%06', '%07',
     '%08', '%09', '%0a', '%0b', '%0c', '%0d', '%0e', '%0f',
     '%10', '%11', '%12', '%13', '%14', '%15', '%16', '%17',
     '%18', '%19', '%1a', '%1b', '%1c', '%1d', '%1e', '%1f',
     '%20', '%21', '%22', '%23', '%24', '%25', '%26', '%27',
     '%28', '%29', '%2a', '%2b', '%2c', '%2d', '%2e', '%2f',
     '%30', '%31', '%32', '%33', '%34', '%35', '%36', '%37',
     '%38', '%39', '%3a', '%3b', '%3c', '%3d', '%3e', '%3f',
     '%40', '%41', '%42', '%43', '%44', '%45', '%46', '%47',
     '%48', '%49', '%4a', '%4b', '%4c', '%4d', '%4e', '%4f',
     '%50', '%51', '%52', '%53', '%54', '%55', '%56', '%57',
     '%58', '%59', '%5a', '%5b', '%5c', '%5d', '%5e', '%5f',
     '%60', '%61', '%62', '%63', '%64', '%65', '%66', '%67',
     '%68', '%69', '%6a', '%6b', '%6c', '%6d', '%6e', '%6f',
     '%70', '%71', '%72', '%73', '%74', '%75', '%76', '%77',
     '%78', '%79', '%7a', '%7b', '%7c', '%7d', '%7e', '%7f',
     '%80', '%81', '%82', '%83', '%84', '%85', '%86', '%87',
     '%88', '%89', '%8a', '%8b', '%8c', '%8d', '%8e', '%8f',
     '%90', '%91', '%92', '%93', '%94', '%95', '%96', '%97',
     '%98', '%99', '%9a', '%9b', '%9c', '%9d', '%9e', '%9f',
     '%a0', '%a1', '%a2', '%a3', '%a4', '%a5', '%a6', '%a7',
     '%a8', '%a9', '%aa', '%ab', '%ac', '%ad', '%ae', '%af',
     '%b0', '%b1', '%b2', '%b3', '%b4', '%b5', '%b6', '%b7',
     '%b8', '%b9', '%ba', '%bb', '%bc', '%bd', '%be', '%bf',
     '%c0', '%c1', '%c2', '%c3', '%c4', '%c5', '%c6', '%c7',
     '%c8', '%c9', '%ca', '%cb', '%cc', '%cd', '%ce', '%cf',
     '%d0', '%d1', '%d2', '%d3', '%d4', '%d5', '%d6', '%d7',
     '%d8', '%d9', '%da', '%db', '%dc', '%dd', '%de', '%df',
     '%e0', '%e1', '%e2', '%e3', '%e4', '%e5', '%e6', '%e7',
     '%e8', '%e9', '%ea', '%eb', '%ec', '%ed', '%ee', '%ef',
     '%f0', '%f1', '%f2', '%f3', '%f4', '%f5', '%f6', '%f7',
     '%f8', '%f9', '%fa', '%fb', '%fc', '%fd', '%fe', '%ff');
 var
   iLen,iIndex : integer;
   stEncoded : string;
   ch : widechar;
 begin
   iLen := Length(stInput);
   stEncoded := '';
   for iIndex := 1 to iLen do
   begin
     ch := stInput[iIndex];
     if (ch >= 'A') and (ch <= 'Z') then
       stEncoded := stEncoded + ch
     else if (ch >= 'a') and (ch <= 'z') then
       stEncoded := stEncoded + ch
     else if (ch >= '0') and (ch <= '9') then
       stEncoded := stEncoded + ch
     else if (ch = ' ') then
       stEncoded := stEncoded + '+'
     else if ((ch = '-') or (ch = '_') or (ch = '.') or (ch = '!') or (ch = '*')
       or (ch = '~') or (ch = '\')  or (ch = '(') or (ch = ')')) then
       stEncoded := stEncoded + ch
     else if (Ord(ch) <= $07F) then
       stEncoded := stEncoded + hex[Ord(ch)]
     else if (Ord(ch) <= $7FF) then
     begin
        stEncoded := stEncoded + hex[$c0 or (Ord(ch) shr 6)];
        stEncoded := stEncoded + hex[$80 or (Ord(ch) and $3F)];
     end
     else
     begin
        stEncoded := stEncoded + hex[$e0 or (Ord(ch) shr 12)];
        stEncoded := stEncoded + hex[$80 or ((Ord(ch) shr 6) and ($3F))];
        stEncoded := stEncoded + hex[$80 or ((Ord(ch)) and ($3F))];
     end;
   end;
   result := (stEncoded);
 end;

source : Java source code

Answer 5

I made myself this function to encode everything except really safe characters. Especially I had problems with +. Be aware that you can not encode the whole URL with this function but you need to encdoe the parts that you want to have no special meaning, typically the values of the variables.

function MyEncodeUrl(source:string):string;
 var i:integer;
 begin
   result := '';
   for i := 1 to length(source) do
       if not (source[i] in ['A'..'Z','a'..'z','0','1'..'9','-','_','~','.']) then result := result + '%'+inttohex(ord(source[i]),2) else result := result + source[i];
 end;

Answer 6

In a non-dotnet environment, the Wininet unit provides access to Windows' WinHTTP encode function: InternetCanonicalizeUrl