출처 : http://koti.mbnet.fi/akini/delphi/urldecodeutf8/
Always use UTF8 or unicode strings if possible
Java and dotNet coders don't have to do anything special but "native language" coders must do few extra steps to overcome unicode problems.
Here is URLDecodeUTF8(ansistr, widestr) conversion method and example UI application. I have taken inspiration from Indy urldecode function and converted it to widechar enabled function. Indy urldecode support only string and legacy charset encoded strings.
Here is full sources and example UI exe to try it out. I have created dll library because I need to call it from c++ program. You can copypaste code to suit your needs. Test application uses TntUnicode components, see reference image.
orcoredll.zip sources and exe
dlltest.png reference image
Convert UTF8 encoded ansi string to widestring:
unit orcoredll_unit1;
interface
// unit's public functions. use "C-style" stdcall stack
// for better compatibility to other applications.
function WideStringToAnsiString(const pw: PWideChar; const buf: PAnsiChar;
var lenBuf: Cardinal): boolean; stdcall;
function URLDecodeUTF8(const s: PAnsiChar; const buf: PWideChar;
var lenBuf: Cardinal): boolean; stdcall;
function URLDecodeUTF8A(const s: PAnsiChar; const buf: PAnsiChar;
var lenBuf: Cardinal): boolean; stdcall;
implementation
uses SysUtils;
{
Convert unicode WideString to AnsiString
@param pw widestring to be converted
@outparam buf buffer for resulting ansistring
@outparam lenBuf number of characters in buffer
@return true if conversion was done or false
if only lenBuf was updated
}
function WideStringToAnsiString(const pw: PWideChar; const buf: PAnsiChar;
var lenBuf: Cardinal): boolean; stdcall;
var
sa: AnsiString;
len: Cardinal;
begin
sa := WideCharToString(pw);
len := Length(sa);
if Assigned(buf) and (len < lenBuf) then begin
// copy result into the buffer, buffer must have
// space for last null byte.
// lenBuf=num of chars in buffer, not counting null
if (len > 0) then
Move(PAnsiChar(sa)^, buf^, len * SizeOf(AnsiChar));
buf[len] := #0;
lenBuf := len;
Result := True;
end else begin
// tell calling program how big the buffer
// shoule be to store all decoded characters,
// including trailing null value.
if (len > 0) then
lenBuf := len+1;
Result := False;
end;
end;
{
URLDecode utf8 encoded string. Resulting widestring
is copied to inout 'buf' buffer.
@param s encoded string
@outparam buf buffer for decoded string or nil
if should update lenBuf only
@outparam lenBuf num of characters stored to buffer
@return true if string was decoder or false
if only lenBuf was updated.
}
function URLDecodeUTF8(const s: PAnsiChar; const buf: PWideChar;
var lenBuf: Cardinal): boolean; stdcall;
var
sAnsi: String; // normal ansi string
sUtf8: String; // utf8-bytes string
sWide: WideString; // unicode string
i, len: Cardinal;
ESC: string[2];
CharCode: integer;
c: char;
begin
sAnsi := s; // null-terminated str to pascal str
SetLength(sUtf8, Length(sAnsi));
// Convert URLEncoded str to utf8 str, it must
// use utf8 hex escaping for non us-ascii chars
// + = space
// %2A = *
// %C3%84 = ? (A with diaeresis)
i := 1;
len := 1;
while (i <= Cardinal(Length(sAnsi))) do begin
if (sAnsi[i] <> '%') then begin
if (sAnsi[i] = '+') then begin
c := ' ';
end else begin
c := sAnsi[i];
end;
sUtf8[len] := c;
Inc(len);
end else begin
Inc(i); // skip the % char
ESC := Copy(sAnsi, i, 2); // Copy the escape code
Inc(i, 1); // skip ESC, another +1 at end of loop
try
CharCode := StrToInt('$' + ESC);
//if (CharCode > 0) and (CharCode < 256) then begin
c := Char(CharCode);
sUtf8[len] := c;
Inc(len);
//end;
except end;
end;
Inc(i);
end;
Dec(len); // -1 to fix length (num of characters)
SetLength(sUtf8, len);
sWide := UTF8Decode(sUtf8); // utf8 string to unicode
len := Length(sWide);
if Assigned(buf) and (len < lenBuf) then begin
// copy result into the buffer, buffer must have
// space for last null byte.
// lenBuf=num of chars in buffer, not counting null
if (len > 0) then
Move(PWideChar(sWide)^, buf^, len * SizeOf(WideChar));
buf[len] := #0;
lenBuf := len;
Result := True;
end else begin
// tell calling program how big the buffer
// should be to store all decoded characters,
// including trailing null value.
if (len > 0) then
lenBuf := len+1;
Result := False;
end;
end;
{
URLDecode utf8 encoded string. Resulting ansistring
is copied to inout 'buf' buffer.
@param s encoded string
@outparam buf buffer for decoded string or nil
if should update lenBuf only
@outparam lenBuf num of characters stored to buffer
@return true if string was decoder or false
if only lenBuf was updated.
}
function URLDecodeUTF8A(const s: PAnsiChar; const buf: PAnsiChar;
var lenBuf: Cardinal): boolean; stdcall;
var
len: Cardinal;
pw: PWideChar;
ok : boolean;
begin
// decode to widestring
len := lenBuf * SizeOf(WideChar) + 1;
pw := AllocMem(len);
try
ok := URLDecodeUTF8(s, pw, len);
if Not(ok) then begin
lenBuf := len; // num of chars in pw buffer
Result := ok;
Exit;
end;
// convert to ansistring
len := len * SizeOf(AnsiChar) + 1;
ok := WideStringToAnsiString(pw, buf, len);
lenBuf := len;
Result := ok;
finally
FreeMem(pw);
end;
end;
end.
And then external application may use dll functions.
procedure TForm1.Button2Click(Sender: TObject);
var
pw: PWideChar;
pa: PAnsiChar;
sa: AnsiString;
sw: WideString;
len: Cardinal;
begin
sw := edtParam.Text;
sa := sw;
// allocate mem for inout widechar buffer +1 for NULL
// widechar takes 2 bytes (16bit unicode char)
len := Length(sa) * SizeOf(WideChar) + 1;
pw := AllocMem(len);
try
URLDecodeUTF8(PAnsiChar(sa), pw, len);
sw := pw; // copy PWideChar to WideString
finally
FreeMem(pw);
end;
memo.Lines.Add(sw + ', len: ' + IntToStr(len));
// allocate mem for inout ansichar buffer +1 for NULL
// ansichar takes one byte (8bit char)
len := Length(sw) * SizeOf(AnsiChar) + 1;
pa := AllocMem(len);
try
pw := PWideChar(sw);
WideStringToAnsiString(pw, pa, len);
sa := pa; // copy PAnsiChar to AnsiString
finally
FreeMem(pa);
end;
memo2.Lines.Add(sa + ', len: ' + IntToStr(len));
// decode directly to AnsiString
sw := edtParam.Text;
sa := sw;
len := Length(sa) * SizeOf(AnsiChar) + 1;
pa := AllocMem(len);
try
URLDecodeUTF8A(PAnsiChar(sa), pa, len);
sa := pa; // copy PAnsiChar to AnsiString
finally
FreeMem(pa);
end;
memo2.Lines.Add(sa + ', Alen: ' + IntToStr(len));
end;
