Urldecode in batch file - url

Question

How can I 'urldecode' the following string in a batch file? I need to change the following
http://www.example.com/some-page/some/link.html
to this
http://www.example.com/some-page/some/link.html
It can be done in Javascript with decodeURIComponent() but I've no idea how to do it in a batch file just within MSDOS etc.

Answer 1

It can be done in Javascript with decodeURIComponent() but I've no idea how to do it in a batch file just within MSDOS etc.
Not with decodeURIComponent(), no. Be that as it may, the solution still lies with invoking JavaScript. You can call on the IE7 JavaScript engine via JScript. See this page for more examples of batch + JScript hybrid scripts.
There are no built-in JavaScript functions to convert HTML entities (the ÿ characters) back to plain text, but it's not too difficult to roll your own.
#if (#CodeSection == #Batch) #then
:: batch portion
#echo off
setlocal
set "url=http://www.example.com/some-page/some/link.html"
cscript /nologo /e:JScript "%~f0" "%url%"
goto :EOF
#end
// JScript portion
function decodeEntities(what) {
return what.replace(/&#x([0-9a-f]{2});/ig, function(m, $1) {
return String.fromCharCode(parseInt($1, 16));
});
}
WSH.Echo(decodeEntities(WSH.Arguments(0)));
Just as an academic exercise, here's a pure batch method of converting HTML character entities to ASCII. It's slightly slower than the JScript hybrid, and it'll probably mistreat strings containing exclamation marks.
#echo off
setlocal enabledelayedexpansion
set "url=http://www.example.com/some-page/some/link.html"
set "url=%url:&#x=;0x%"
:begin
for %%I in (%url%) do (
set "chunk=%%~I"
if "!chunk:~0,2!"=="0x" if "!chunk:~4,1!"=="" (
for /f "delims=" %%x in (
'forfiles /m "%~nx0" /c "cmd /c echo(%%~I"'
) do set "url=!url:;%%I;=%%~x!"
goto begin
)
)
)
echo !url!

Answer 2

This may be achieved in pure Batch...
#echo off
setlocal EnableDelayedExpansion
set "input=http://www.example.com/some-page/some/link.html"
rem Define the equivalences
for %%a in ("#x3a=:" "#x2f=/") do (
for /F "tokens=1,2 delims==" %%b in (%%a) do set "replace[%%b]=%%c"
)
echo Input = "%input%"
set "input=%input:&=\%"
set "output="
for %%a in (%input%) do (
for /F "tokens=1,2 delims=\" %%b in ("%%a") do (
if "%%c" neq "" (
set "output=!output!%%b!replace[%%c]!"
) else (
set "term=%%a"
if "!term:~0,1!" equ "\" (
set "output=!output!!replace[%%b]!"
) else (
set "output=!output!%%b"
)
)
)
)
echo Output = "%output%"

Answer 3

#if (#x)==(#y) #end /***** jscript comment ******
#echo off
set "url=http://www.example.com/some-page/some/link.html"
cscript //E:JScript //nologo "%~f0" "%url%"
exit /b 0
#if (#x)==(#y) #end ****** end comment *********/
var args=WScript.Arguments;
//WScript.Echo(args.Item(0));
WScript.Echo(decodeURIComponent(args.Item(0)));
though this definitely is not uri encoded url...