function DigitToHex(Digit: Integer): Char;
begin
case Digit of
0..9: Result := Chr(Digit + Ord('0'));
10..15: Result := Chr(Digit - 10 + Ord('A'));
else
Result := '0';
end;
end; // DigitToHex
function URLEncode(const S: string): string;
var
i, idx, len: Integer;
begin
len := 0;
for i := 1 to Length(S) do
if ((S[i] >= '0') and (S[i] <= '9')) or
((S[i] >= 'A') and (S[i] <= 'Z')) or
((S[i] >= 'a') and (S[i] <= 'z')) or (S[i] = ' ') or
(S[i] = '_') or (S[i] = '*') or (S[i] = '-') or (S[i] = '.') then
len := len + 1
else
len := len + 3;
SetLength(Result, len);
idx := 1;
for i := 1 to Length(S) do
if S[i] = ' ' then
begin
Result[idx] := '+';
idx := idx + 1;
end
else if ((S[i] >= '0') and (S[i] <= '9')) or
((S[i] >= 'A') and (S[i] <= 'Z')) or
((S[i] >= 'a') and (S[i] <= 'z')) or
(S[i] = '_') or (S[i] = '*') or (S[i] = '-') or (S[i] = '.') then
begin
Result[idx] := S[i];
idx := idx + 1;
end
else
begin
Result[idx] := '%';
Result[idx + 1] := DigitToHex(Ord(S[i]) div 16);
Result[idx + 2] := DigitToHex(Ord(S[i]) mod 16);
idx := idx + 3;
end;
end; // URLEncode
function URLDecode(const S: string): string;
var
i, idx, len, n_coded: Integer;
function WebHexToInt(HexChar: Char): Integer;
begin
if HexChar < '0' then
Result := Ord(HexChar) + 256 - Ord('0')
else if HexChar <= Chr(Ord('A') - 1) then
Result := Ord(HexChar) - Ord('0')
else if HexChar <= Chr(Ord('a') - 1) then
Result := Ord(HexChar) - Ord('A') + 10
else
Result := Ord(HexChar) - Ord('a') + 10;
end;
begin
len := 0;
n_coded := 0;
for i := 1 to Length(S) do
if n_coded >= 1 then
begin
n_coded := n_coded + 1;
if n_coded >= 3 then
n_coded := 0;
end
else
begin
len := len + 1;
if S[i] = '%' then
n_coded := 1;
end;
SetLength(Result, len);
idx := 0;
n_coded := 0;
for i := 1 to Length(S) do
if n_coded >= 1 then
begin
n_coded := n_coded + 1;
if n_coded >= 3 then
begin
Result[idx] := Chr((WebHexToInt(S[i - 1]) * 16 +
WebHexToInt(S[i])) mod 256);
n_coded := 0;
end;
end
else
begin
idx := idx + 1;
if S[i] = '%' then
n_coded := 1;
if S[i] = '+' then
Result[idx] := ' '
else
Result[idx] := S[i];
end;
end; // URLDecode